Abstract

Quantifying the coloration and luminous transmittance of eyewear filters is essential to understand their impact on human visual performance. Accurate measurements require the use of a spectrophotometer, with such equipment often being prohibitively expensive for wide-scale use. This paper details a new technique to characterize eyewear filters using only a digital camera and a sheet of white paper. Images of the paper are captured with and without the filter in front of the camera lens, and then subsequent analysis of pixel intensities allows the filter coloration and luminous transmittance to be determined. The technique has been applied to six different eyewear filters using three different camera and illumination configurations, demonstrating a reasonable match to the spectrophotometer data. This technique is suited to implementation in a smartphone app, in order to provide a low-cost and widely deployable solution to monitor the ageing of eyewear inventory.

Full Article  |  PDF Article
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References

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  1. F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
    [Crossref]
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    [Crossref]
  3. J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
    [Crossref]
  4. British Standards Institution, “Personal eye-protection equipment–filters and eye-protectors against laser radiation (laser eye-protectors),” (2009).
  5. V. Brown, Cool Shades: The History and Meaning of Sunglasses (Bloomsbury Academic, 2015).
  6. C. A. Williamson and M. Y. Boontanrart, “Simulating the impact of laser eye protection on color vision,” J. Laser Appl. 28, 012010 (2016).
    [Crossref]
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    [Crossref]
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  9. G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
    [Crossref]
  10. A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
    [Crossref]
  11. P. B. Pathare, U. L. Opara, and F. A. J. Al-Said, “Colour measurement and analysis in fresh and processed foods: a review,” Food Bioprocess Technol. 6, 36–60 (2013).
    [Crossref]
  12. M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
    [Crossref]
  13. M. Stokes, M. Anderson, S. Chandrasekar, and R. Motta, “A standard default color space for the Internet: sRGB,” International Color Consortium, 1996, http://color.org/sRGB.xalter .
  14. British Standards Institution, “Multimedia system and equipment—Colour measurement and management—Part 2-1: Colour management—Default RGB colour space—sRGB,” (2000).
  15. International Telecommunication Union, “Studio encoding parameters of digital television for standard 4:3 and wide-screen 16:9 aspect ratios,” Recommendation (2011).
  16. G. Wyszecki and W. S. Stiles, Color Science, 2nd ed. (Wiley, 1982).
  17. British Standards Institution, “Personal protective equipment—Test methods for sunglasses and related eyewear,” (2013).
  18. International Commission on Illumination, “A colour appearance model for colour management systems: CIECAM02,” (2004).

2017 (2)

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

2016 (1)

C. A. Williamson and M. Y. Boontanrart, “Simulating the impact of laser eye protection on color vision,” J. Laser Appl. 28, 012010 (2016).
[Crossref]

2014 (3)

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

J. C. S. Yam and A. K. H. Kwok, “Ultraviolet light and ocular diseases,” Int. Ophthalmol. 34, 383–400 (2014).
[Crossref]

2013 (1)

P. B. Pathare, U. L. Opara, and F. A. J. Al-Said, “Colour measurement and analysis in fresh and processed foods: a review,” Food Bioprocess Technol. 6, 36–60 (2013).
[Crossref]

2000 (1)

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

1995 (1)

Al-Said, F. A. J.

P. B. Pathare, U. L. Opara, and F. A. J. Al-Said, “Colour measurement and analysis in fresh and processed foods: a review,” Food Bioprocess Technol. 6, 36–60 (2013).
[Crossref]

Anderson, M.

M. Stokes, M. Anderson, S. Chandrasekar, and R. Motta, “A standard default color space for the Internet: sRGB,” International Color Consortium, 1996, http://color.org/sRGB.xalter .

Atwater, J.

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Baillet, G.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Behar-Cohen, F.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Boontanrart, M. Y.

C. A. Williamson and M. Y. Boontanrart, “Simulating the impact of laser eye protection on color vision,” J. Laser Appl. 28, 012010 (2016).
[Crossref]

Brown, V.

V. Brown, Cool Shades: The History and Meaning of Sunglasses (Bloomsbury Academic, 2015).

Brubaker, K. B.

L. A. Levasseur, J. F. Roach, and K. B. Brubaker, “Evaluation of laser-protective eyewear dyes in UVEX lenses,” (US Army Natick Research Development and Engineering Center, 1994).

Burks, R. M.

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Chandrasekar, S.

M. Stokes, M. Anderson, S. Chandrasekar, and R. Motta, “A standard default color space for the Internet: sRGB,” International Color Consortium, 1996, http://color.org/sRGB.xalter .

Cochrane, A. L.

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

da Cruz Vasoncellos, F.

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

de Ayguavives, T.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Garcia-Melendrez, A.

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

Holmes, A. E.

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Hoorfar, M.

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

Ikonen, E.

Kangas, M. J.

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Kawchuk, J.

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

Khoo, H.

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

Krutmann, J.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Kwok, A. K. H.

J. C. S. Yam and A. K. H. Kwok, “Ultraviolet light and ocular diseases,” Int. Ophthalmol. 34, 383–400 (2014).
[Crossref]

Levasseur, L. A.

L. A. Levasseur, J. F. Roach, and K. B. Brubaker, “Evaluation of laser-protective eyewear dyes in UVEX lenses,” (US Army Natick Research Development and Engineering Center, 1994).

Lowe, C. R.

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

Luka, G. S.

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

Lukowicz, R. M.

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Manoochehri, F.

Martinez-Hurtado, J. L.

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

Motta, R.

M. Stokes, M. Anderson, S. Chandrasekar, and R. Motta, “A standard default color space for the Internet: sRGB,” International Color Consortium, 1996, http://color.org/sRGB.xalter .

Najjaran, H.

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

Nowak, E.

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

Opara, U. L.

P. B. Pathare, U. L. Opara, and F. A. J. Al-Said, “Colour measurement and analysis in fresh and processed foods: a review,” Food Bioprocess Technol. 6, 36–60 (2013).
[Crossref]

Ortega Garcia, P.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Pathare, P. B.

P. B. Pathare, U. L. Opara, and F. A. J. Al-Said, “Colour measurement and analysis in fresh and processed foods: a review,” Food Bioprocess Technol. 6, 36–60 (2013).
[Crossref]

Pena-Garcia, P.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Reme, C.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Roach, J. F.

L. A. Levasseur, J. F. Roach, and K. B. Brubaker, “Evaluation of laser-protective eyewear dyes in UVEX lenses,” (US Army Natick Research Development and Engineering Center, 1994).

Stiles, W. S.

G. Wyszecki and W. S. Stiles, Color Science, 2nd ed. (Wiley, 1982).

Stokes, M.

M. Stokes, M. Anderson, S. Chandrasekar, and R. Motta, “A standard default color space for the Internet: sRGB,” International Color Consortium, 1996, http://color.org/sRGB.xalter .

Williams, P.

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Williamson, C. A.

C. A. Williamson and M. Y. Boontanrart, “Simulating the impact of laser eye protection on color vision,” J. Laser Appl. 28, 012010 (2016).
[Crossref]

Wolffsohn, J. S.

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

Wu, S.

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

Wyszecki, G.

G. Wyszecki and W. S. Stiles, Color Science, 2nd ed. (Wiley, 1982).

Yam, J. C. S.

J. C. S. Yam and A. K. H. Kwok, “Ultraviolet light and ocular diseases,” Int. Ophthalmol. 34, 383–400 (2014).
[Crossref]

Yetisen, A. K.

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

Yoshimitsu, Y.

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

Appl. Opt. (1)

Clin. Ophthalmol. (1)

F. Behar-Cohen, G. Baillet, T. de Ayguavives, P. Ortega Garcia, J. Krutmann, P. Pena-Garcia, C. Reme, and J. S. Wolffsohn, “Ultraviolet damage to the eye revisited: eye-sun protection factor (E-SPF), a new ultraviolet protection label for eyewear,” Clin. Ophthalmol. 8, 87–104 (2014).
[Crossref]

Crit. Rev. Anal. Chem. (1)

M. J. Kangas, R. M. Burks, J. Atwater, R. M. Lukowicz, P. Williams, and A. E. Holmes, “Colorimetric sensor arrays for the detection and identification of chemical weapons and explosives,” Crit. Rev. Anal. Chem. 47, 138–153 (2017).
[Crossref]

Food Bioprocess Technol. (1)

P. B. Pathare, U. L. Opara, and F. A. J. Al-Said, “Colour measurement and analysis in fresh and processed foods: a review,” Food Bioprocess Technol. 6, 36–60 (2013).
[Crossref]

Int. Ophthalmol. (1)

J. C. S. Yam and A. K. H. Kwok, “Ultraviolet light and ocular diseases,” Int. Ophthalmol. 34, 383–400 (2014).
[Crossref]

J. Laser Appl. (1)

C. A. Williamson and M. Y. Boontanrart, “Simulating the impact of laser eye protection on color vision,” J. Laser Appl. 28, 012010 (2016).
[Crossref]

Optom. Vision Sci. (1)

J. S. Wolffsohn, A. L. Cochrane, H. Khoo, Y. Yoshimitsu, and S. Wu, “Contrast is enhanced by yellow lenses because of selective reduction of short-wavelength light,” Optom. Vision Sci. 77, 73–81 (2000).
[Crossref]

Royal Soc. Open Sci. (1)

G. S. Luka, E. Nowak, J. Kawchuk, M. Hoorfar, and H. Najjaran, “Portable device for the detection of colorimetric assays,” Royal Soc. Open Sci. 4, 171025 (2017).
[Crossref]

Sens. Actuators B: Chem. (1)

A. K. Yetisen, J. L. Martinez-Hurtado, A. Garcia-Melendrez, F. da Cruz Vasoncellos, and C. R. Lowe, “A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests,” Sens. Actuators B: Chem. 196, 156–160 (2014).
[Crossref]

Other (9)

L. A. Levasseur, J. F. Roach, and K. B. Brubaker, “Evaluation of laser-protective eyewear dyes in UVEX lenses,” (US Army Natick Research Development and Engineering Center, 1994).

British Standards Institution, “Personal eye-protection equipment–filters and eye-protectors against laser radiation (laser eye-protectors),” (2009).

V. Brown, Cool Shades: The History and Meaning of Sunglasses (Bloomsbury Academic, 2015).

M. Stokes, M. Anderson, S. Chandrasekar, and R. Motta, “A standard default color space for the Internet: sRGB,” International Color Consortium, 1996, http://color.org/sRGB.xalter .

British Standards Institution, “Multimedia system and equipment—Colour measurement and management—Part 2-1: Colour management—Default RGB colour space—sRGB,” (2000).

International Telecommunication Union, “Studio encoding parameters of digital television for standard 4:3 and wide-screen 16:9 aspect ratios,” Recommendation (2011).

G. Wyszecki and W. S. Stiles, Color Science, 2nd ed. (Wiley, 1982).

British Standards Institution, “Personal protective equipment—Test methods for sunglasses and related eyewear,” (2013).

International Commission on Illumination, “A colour appearance model for colour management systems: CIECAM02,” (2004).

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Figures (3)

Fig. 1.
Fig. 1. Example reference white image, using smartphone setup A.
Fig. 2.
Fig. 2. Example image through the “orange” filter, using smartphone setup A.
Fig. 3.
Fig. 3. Comparison of luminous transmittance for the six filters and three measurement conditions. Error bars for smartphone setup B represent standard deviations for three sets of images.

Tables (2)

Tables Icon

Table 1. Camera and Illumination Parameters

Tables Icon

Table 2. Experimental Results for Coloration and Luminous Transmittance

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

( r , g , b ) = ( ( R , G , B ) / 12.92 ( ( R , G , B ) + 0.055 / 1.055 ) 2.4 ( R , G , B ) 0.04045 ( R , G , B ) > 0.04045 ) .
( r scale , g scale , b scale ) = 1 ( r white , g white , b white ) .
( R , G , B ) = ( 12.92 ( r , g , b ) 1.055 ( r , g , b ) 1 2.4 0.055 ( r , g , b ) 0.0031308 ( r , g , b ) > 0.0031308 ) ,
T = 0.299 r filter + 0.587 g filter + 0.114 b filter ,

Metrics