近年來，許多LED產品由於節能，以及效率較傳統光源高而在市面上被廣泛運用，取代了傳統的光源，包括室內照明、室外照明、道路照明等用途，在相關產業上更是佔有舉足輕重的角色。但是相較於傳統光源，由點光源組成的LED產品，在使用上易造成光源發光面的亮度不均勻、眩光等問題，而導致過去使用在評價眩光的統一眩光公式 (Unified Glare Rating, UGR)已不再適用於LED光源。
本研究共設計兩個實驗來探討使用次波長金屬光柵 (偏光片)應用在LED產品上對於視覺舒適度的影響。實驗一利用二維色度儀量測出使用偏光片與無使用偏光片在光源發光面上的均勻度。實驗二則是在不同環境條件下利用主觀視覺評價的方式，評價LED燈具來分析偏光片使用後對於視覺舒適度的影響，此外在實驗二的進行前/進行後階段，使用閃光融合儀量測出觀測者生理的視覺疲勞程度後將兩數據相減再以主觀問卷的方式詢問，分析生理評價與主觀評價兩者的相關度是否為顯著，以此數據做為篩選觀測者數據穩定性之依據。最後將利用實驗的結果對原本CIE所定義的統一眩光指數的公式UGR進行修正，以提高原本UGR預測LED不均勻光源的準確性為目的，加入對比以及光源最大亮度的參數，得到新的預測眩光公式C-UGR (Contrast UGR)。

Because of energy saving and efficiency, people would like to use LED as the parts of the products in recent years, instead of using traditional light sources. However, in agreement with earlier work, it can be concluded that point-array type of LED luminaires could provoke more discomfort glare, non-uniform emitting surface than traditional light sources. In this study, two experiments were designed to analyze visual comfort effect and visual fatigue degree of the white LEDs with / without nano-wire grid polarizer. A novel 2D colorimeter was used to analyze the uniformity of the two lighting types (polarized and unpolarized LEDs) in the first experiment. In the second experiment, a visual assessment way was used to analyze visual comfort degrees under different conditions between two lighting types. Critical flicker fusion (CFF) method was utilized to analysis the degrees of physiologically visual fatigue before and after experiment, then the participants were asked to answer subjectively visual fatigue questionnaire. The aim of the second experiment was to find the relation between the subjective assessment and the physiological assessment. Finally the results were tested for adjusting the Unified Glare Rating formula defined by CIE. And the goal is to derivate the modified formula for non-uniform white LED arrays, which is named C-UGR(Contrast UGR).

[1]J. R. Biard, et al., “GaAs Infrared Source,” International Electron Devices Meeting, Washington, pp. 96 (1962).
[2]CIE, “Techinical report Discomfort Glare in Interior Lighting,” WG Julian, (1995).
[3]J. C. Su and T. M. Lin, “Polarized white light emitting diodes with a nano-wire grid polarizer,” Optics Express., Vol.21, No.1 pp.840-845 (2013).
[4]Metrology, I. C. F. D., Information Display Measurements Standard., Society for Information Display, pp. 317-319 (2012)
[5]黃日鋒, et al., 顯示色彩工程學, 台北： 全華圖書股份有限公司(2011).
[6]M. Kalloniatis, C. Luu, Psychophysics of Vision by Michael Kalloniatis and Charles, The organization of the retina and visual system (1995).
[7]G. A. Geischeider, Psychophysics： The Fundamentals. 3rd ed. New Jersey： Lawrence Erlbaum Associates, Inc., Publishers (1997).
[8]G. C. H., Vision and Visual Perception. New York： John Wiley and Sons, Inc (1965).
[9]CIE, Lighting of Indoor Work Places.： Vienna, Austria (2002).
[10]M. Luckiesh and S. K. Guth, “Brightness in Visual Field at Borderline Between Comfort and Discomfort,“ In Illuminating Engineering, pp.650-670 (1949).
[11]R. G. Hopkinson, “Glare from daylighting in buildings,” Applied Ergonomics, Vol.3, No.4, pp. 206-215 (1972).
[12]W. K. E. Osterhaus, “Discomfort glare assessment and prevention for daylight applications in office environments,” Solar Energy, Vol.79： pp. 140-158 (2005).
[13]S. Nakamura, M. Senoh, and T. Mukai, P-GaN/N-InGaN/N, “Double-Heterostructure Blue-Light-Emitting Diodes,” Japan. J. Appl. Phys, Vol.32： pp. 8-11 (1993).
[14]T. Kasahara, et al., “Discomfort Glare Caused by White LED Light Sources,” J. Light & Vis, Env. Vol.30, No. 2. pp. 95-103 (2006).
[15]L. M. Geerdinck, J. R. V. Gheluwe, and M. C. J. M. Vissenberg, “Discomfort glare perception of non-uniform light sources in an office setting,” Journal of Environmental Psychology, pp. 1-9 (2014).
[16]S. Kohko et al., “Glare of LED Lighting in Outdoor Environment,” in CIE x039 (2014).
[17]J. D. Bullough, “Luminance versus luminous intensity as a metric for discomfort glare,” SAE Technical Paper., pp.31-35 (2011).
[18]P. Petherbridge and R. G. Hopkinson, “Discomfort glare and the lighting of buildings,” Trans.Illum.Eng.Soc. Vol.15, pp.39–44 (1950).
[19]J. J. Sammarco, et al., “Discomfort Glare Comparison for Various LED Cap Lamps,” in IEEE Transactions on Industry Applications, Vol.47, No.3, pp.1168-1174 (2011).
[20]J. D. Bullough, et al., “Predicting discomfort glare from outdoor lighting installations,” Lighting Res. Technol, Vol.40, No.3, pp. 225-242 (2008).
[21]P. Ngai and P. Boyce, “The Effect of Overhead Glare on Visual Discomfort,” Journal of the Illuminating Engineering Society., pp.29-38 (2000).
[22]L. Erdem, K. Trampert, and C. Neumann, “Evaluation of Discomfort Glare from LED Lighting Systems,” Journal of Lighting Engineering., Vol.14, pp. 7-26 (2012).
[23]T. T. MSc, et al., “Discomfort glare for white LED light sources with different spatial arrangements,” Lighting Res. Technol, Vol.47, pp. 316-337 (2015).
[24]楊維寧, 統計學 STATISTICS., 台北市： 新陸書局股份有限公司 (2007).
[25]M. Knoop, Lighting Quality with LEDs, in CIE x39 (2012).
[26]C. F. Wu, J. J. Liou, and J. L. Lin, “Evaluation of Visual Performance Using LED Signboards under Different Ambient Conditions,” Sciverse Science Direct, Vol.29, pp. 975-980 (2012).
[27]Y. Wu, et al., “Evaluation Method Research on Discomfort Glare of LED Products,” in CIE x39 (2014).
[28]W. R. Ruckaert, et al., “Performance of LED Linear Replacement Lamps,” in Session of the CIE (2011).
[29]H. S. Gertjan., et al., “Calculation of the Unified Glare Rating based on luminance maps for uniform and non-uniform light sources,”Building and Environment, Vol.84, pp.60-67 (2015).
[30]Y. Lin, et al., “Model Predicting Discomfort Glare Caused by LED Road Lights,” Optics Express, Vol.22, No15, pp.18056-18071 (2014).
[31]Y. Y. Huang, M. Menozzi and E. Zurich, “Effects of Discomfort Glare on Peripheral Visual Attention in a Driving Simulator,” Intelligent Vehicles Symposium IEEE, pp.920-925 (2012).
[32]J. Shuster, “Addressing Glare in Solid-State Lighting, in Eephesus Lighting,” (2014).
[33]S. W. Hsu, C. H. Chen, and Y.-D. Jiaan, “Measurements of UGR of LED Light by a DSLR Colorimeter,” in Fourth International Conference on White LEDs and Solid State Lighting, Vol.8484, No.15, pp.1-6 (2015).