The way that persons from different age groups experience “white light” is investigated. Human eye lens transmission changes spectrally with age and this may influence the way that humans from different ages experiences light. Such a difference may be important in industrial and medical environments. Two different age groups, one group younger than 40 years of age and another group older than 50 years of age were subjected to the same “white” definition task. A conventional single-booth setup was used where observers were able to adjust the intensity of four coloured LED’s. Results of the psychophysical test procedure were used to generate specifications of two light sources, as selected by the two age groups. The two age groups selected two very different light sources when tasked to achieve a “perception” of white. Results show that the older group prefers a source with a colour rendering index number of 89 and the younger group prefers a source with a colour rendering index number of 74. The sources selected by the two age groups specifies correlated colour temperature values of 5150 K for the older age group and 6592 K for the younger group.
age, colour rendering, CCT, LED, white perception
 Aries, M.B.C., Aarts, M.P.J., & Van Hoof, J. (2015). Daylight and Health: A Review of the Evidence and Consequences for the Built Environment. Lighting Research & Technology, 47, 6 - 27.
 Halper, M. (March 2017). Human-centric lighting reduces drug reliance at Danish psychiatric hospital. LEDs Magazine.
 AT Kearney. (July 2013). LightingEurope, German Electrical and Electronic Manufacturers Association (ZVEI). lightingeurope. [Online]. www.lightingeurope.org
 Van Bommel, W.J.V., &Van Den Belt, G.J. (2004). Lighting for Work: A Review of Visual and Biological Effects. Lighting Research & Technology, 36(4), 255 - 269..
 Chader, G.J., & Taylor, A. (2013). Preface: The Aging Eye: Normal Changes, Age-Related Diseases, and Sight-Saving Approaches. Investigative Ophthalmology & Visual Science, 54(14).
 Pokorny, J., Smith, V., & Luttze, M. (1987). Aging of the human lens. APPLIED OPTICS, 26(8).
 Artigas, J.M., Felipe, A., Navea, A., Fandino, A., & Artigas, C. (2012). Spectral Transmission of the Human Crystalline Lens in Adult and Elderly Persons: Color and Total Transmission of Visible Light. Investigative Ophthalmology & Visual Science., 53(7), 4076 - 4084.
 Ohno, Y., & Fein, M. (2013). Vision Experiment on White Light Chromaticity for Lighting. [Online]. http://cltc.ucdavis.edu/sites/default/files/files/publication/2-yoshi-ohno-mira-fein-white-light-chromaticity-vision-experiment.pdf
 Rea, M.S., & Freyssinier, J.P. (2010). Color Rendering: Beyond Pride and Prejudice. Color Research and Application, 35(6), 401 - 409.
 Narendran, N., & Deng, L. (2002). Color Rendering Properties of LED light sources. SPIE Proc, 4776, 61 - 67.
 Fotios, S.A., & Cheal. C. (2007). Evidence For Response Contraction Bias in Side-By-Side Matching tasks. Lighting Research & Technology, 39(2), 159 - 169.
 Houser, K.W., Wei, M., David, A., & Krames, M.R. (2014). Whiteness Perception under LED Illumination. Journal of the Illuminating Engineering Society Of North America., 10, 165 - 180.
 Wei, M., Houser, K.W., David, A., & Krames, M.R. (2014). Perceptual responses to LED illumination with colour rendering indices of 85 and 97. Lighting Research & Technology, 0, 1 - 18.
 McCamy, C.S., & Davidson, M.H. (1976). A Color-Rendition Chart. Journal of Applied Photographic Engineering, 2(3), 95 - 99.
 Zukauskas, A., & Vaicekauskas, R. (2011). LEDs in Lighting with Tailored Color Quality. International Journal of High Speed Electronics and Systems., 20(2), 287 - 301.
 OSRAM. (2013) Thermal Management of Golden Dragon LED. [Online]. https://www.osram-os.com/Graphics/XPic8/00165240_0.pdf/Thermal%20Management%20of%20Golden%20DRAGON%20LED.pdf
 OSRAM. (2014) Reliability of the DRAGON Product Family. [Online]. https://www.osram-os.com/Graphics/XPic8/00165204_0.pdf/Reliability%20of%20the%20DRAGON%20Product%20Family.pdf
 Israel, G.D. (2013). University of Florida. [Online]. https://edis.ifas.ufl.edu/pdffiles/PD/PD00600.pdf
 Schefrin, B.E., & Werner, J.S. (1993). Age-related changes in the color appearance of broadband surfaces. Color Research and Application, 18(6), 380 - 389.
 Elliot, S.L., Hardy, J.L., Webster, M.A., & Werner, J.S. (2007). Aging and blur adaptation. Journal of Vision, 7(6).
 Sandor, N., & Schanda, J. (2006). Visual Colour-Rendering Experiments. Lighting Research & Technology, 38(3), 225-239.
 Spaulding, J.M., Thompson, M.R., & Levin, R.E. (2011). Human Preference in Tunable Solid State Lighting.," SPIE Proc., 7954, 795403-1 to 795403-11.
 Thompson, M., O'Reilly, U., & Levin, R.E. (2007). Psychophysical Evaluations of Various Color Rendering from LED-based Architectural Lighting. SPIE Proc., 6669, 66690Y-1 to 66690Y-12..
 Dangol, R., Islam, M., Hyvarinen, M., Bhusal, P., Puolakka, M., & Halonen, L. (2013). Subjective Preferences and Colour Quality Metrics of LED Light Sources. Lighting Research & Technology, 45, 666 - 688.
 Islam, M., Dangol, R., Hyvarinen, M., Bhusal, P., Puolakka, M., & Halonen, L. (2013). User Preferences for LED Lighting in Terms of Light Spectrum. Lighting Research & Technology, 45, 641 - 665.
 OSRAM Tools & Resources. [Online]. www.osram-americas.com/en-us/tools-and-resources/Pages/led-color-calculator.aspx
 Houser, K., Mossman, M., Smet, K., & Whitehead, L. (2015). Tutorial: Color Rendering and its Applications in Lighting. Leukos: Journal of the Illuminating Engineering Society of North America., 00, 1 - 20.
 Bailey, S.. (2013). LeapFrogLighting. [Online]. http://www.leapfroglighting.com/why-the-led-r9-value-isnt-important/
 Ohno, Y. (2011). Calculation of CCT and Duv and Practical Conversion Formulae," in CORM 2011 Conference, Gaithersburg MD.
 Padfield, J. (2018). The National Gallery. [Online]. http://research.ng-london.org.uk/scientific/spd/?page=info
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
All International Journal of Sustainable Lighting (IJSL) content is Open Access, meaning it is accessible online without fee under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/4.0). For any reuse, redistribution, or reproduction of a work, users must clarify the license terms under which the work was produced. Neither the text itself nor the ideas presented in it may be used for commercial purposes.