白光LED之視覺生理效應評估

Evaluation of Visual Physiological Effects of White-light LEDs

謝品萱(Pin-hsuan Hsieh)

指導教授 ： 陳怡君

國立中央大學/理學院/光電科學研究所/碩士(2011年)

摘要

鑑於LED在照明上的諸多優點，如：體積小、發光效率佳、壽命長、無汞污染等因素，且在節能、環保、安全性上皆優於傳統燈泡與日光燈管，使得LED照明燈具開發及其照明設計應用等，皆為極具潛力的研發議題。由於LED發光面積集中、光源具指向性以及白光LED光源頻譜常有藍光峰值等特點，使LED燈具容易衍生干擾視覺的眩光。本論文利用研究團隊已建立之視覺舒適度測試環境與實驗流程，經由心理物理學實驗，比較傳統日光燈管與白光LED燈具之不適眩光，以問卷方式獲得視覺舒適度之主觀評量，以閃光融合閾值量測作為視覺疲勞度的指標。
　　實驗使用閃光融合儀、視力檢查儀、問卷等方式進行數據蒐集，將數據匯入統計軟體SPSS中分析。結果顯示，改變燈具種類（LED、傳統日光燈）有影響人眼主觀辨識度的趨勢，以LED燈具表現較差，但尚未達統計顯著水準，將持續進行實驗驗證。改變工作面照度（1163 lux、872 lux、490 lux），會影響人眼主觀辨識度、主觀視覺環境干擾以及主觀環境偏好等三項指標，其中以490 lux此亮度表現最差，1163 lux、872 lux則無顯著差異。

關鍵字

LED光源頻譜 ； 眩光 ； 視覺舒適度 ； 視覺疲勞度

並列摘要

Light-emitting diodes (LEDs) are a good candidate for next-generation lighting due to their numerous advantages over the traditional lighting installations, such as small volume, longlife time, high efficiency and no mercury pollution. The potential in energy saving, safety, and environmental protection has made the development and applications of LEDs an emerging research area.
　　Due to the distinct characteristics of LEDs from conventional light sources, such as the source size, the radiant direction and the spectral content, LED lamps are more probable to induce glare that disturbs human’s visual sensation. This thesis aims to investigate the discomfort glare effects of white-light LEDs compared to the traditional fluorescent tubes. By utilizing the evaluation platform and the experimental procedure previously established in the research group, psychophysical experiments were performed to obtain subjective ratings of visual comfort through questionnaires and objective scores on visual fatigue from the critical flicker fusion (CFF) measurements.
　　Experimental results showed that changing lamp types (fluorescent lamps and LED lamps) did not affect human visual performance in the aspects considered in this study. There is a trend that subjects felt difficult to concentrate on reading and felt visual fatigue when LED lamps were used, but the data has not reached statistical significance. More subjects will be recruited to verify this issue in follow up studies.
　　Changing the illuminance level (1163 lux, 872 lux, or 490 lux) affected three factors in subjective ratings: recognition, visual disturbances, and lighting environmental preference. Higher illuminance yielded better subjective ratings, while brightness level 1 (1163 lux) and level 2 (872 lux) showed no statistical differences. Hence it is advantageous to increase the illuminance level and 872 lux is sufficiently high for energy saving consideration.

並列關鍵字

visual fatigue ； visual comfort ； glare ； LED spectrum

參考文獻

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