不同白光發光二極體照明工作環境對人的視覺疲勞影響之研究

Abstract

眼睛是人類接收外界資訊主要的感官，約有80%的外界訊息需靠雙眼的視覺來獲取。在這高用眼的時代，用眼過度成為視覺疲勞主要的原因，如加上有不當外在照明環境，更會加速視覺疲勞的程度進而影響工作效率。現今室內環境照明使用發光二極體光源情況日益普及，相對於傳統螢光燈技術，發光二極體功率佳、使用壽命更長及省電。但其照明效果的性質是複雜的，因此新的照明技術對現代人的生、心理影響已成為不得不重視的課題之一。 本實驗以模擬一般辦公室場域及工作模式做為實驗架構。以白光發光二極體為實驗光源，其實驗光照條件分別為：二種色溫(400K/6000K)、二種照度(400lux/700lux)、三種藍光主波長(420nm/460nm/480nm)。實驗對象以青年勞工為主，有6男及6女，共12人(平均23.67±0.62)。實驗流程分別：閱讀、是-否試驗、校對。實驗過程中全程使用生理訊號儀器記錄生理訊號的變化。透過腦電圖、心電圖、眼電圖與閃光融合儀等記錄，分析受測者的腦波、心率變異度、眨眼次數與閃光融合閾值並搭配主觀視覺疲勞問卷找出降低視覺疲勞的白光發光二極體光源。 如何能在保有高工作效率且又能降低視覺疲勞兩者之間取得平衡點是我們研究的目標。本研究結果得到低色溫、低照度及460nm藍光波長的白光發光二極體光源下對於視覺疲勞影響程度小是降低視覺疲勞主要選擇。

Eyes are human’s main sense organ to receive information from outside world. The vision of the eyes receives roughly eighty percent of outside messages. In the era of high use of the eyes, excessive uses of the eyes become the main cause of visual fatigue. For instance, working in an improper external lighting environment would accelerate the degree of visual fatigue and consequently affect work efficiency. Nowadays, it is increasingly popular to take use of LED lighting in indoor environment. Compared to the traditional fluorescent technology, LED lamp possesses superior power and it has greater lifespan and electrical efficiency. The characteristic of lighting effect is complicated. Hence, new lighting technology’s impact upon contemporary people’s life and mental condition has become one of the issues in which deserved to pay attention to. The experimental structure mimics general office field and working mode. White LED was used as experimental light source. The experimental conditions were bicolor temperature (400K / 6000K), two kinds of illuminance (400lux / 700lux), three peak wavelength of blue lights (420nm / 460nm / 480nm) respectively. The subjects are mainly youth workers, literally six men and six women, in total twelve people (average 23.67 ± 0.62). Experimental tasks were reading, Go-No-Go and proofreading. During the full course of the experiment, physiological signal equip is utilized to record changes of physiological signals. Analyze experimental subjects’, heart rate variability (HRV) and blinking rates and critical flicker fusion threshold (CFF) through electroencephalogram (EEG), electrocardiogram (ECG) and electrooculography (EOG), Flicker Fusion System and other records. Couple with questionnaire of subjective visual fatigue to find out a white LED light source in which is able to reduce visual fatigue. How to ensure a balance between the maintenance of high work productivity and reduction of visual fatigue is our research target. This research finding are that low color temperature, low illuminance and white LED with 460nm peak wavelength of blue light light source indeed ensure low degree of visual fatigue, which is the main option to reduce visual fatigue.