以文字與背景的明度對比、字級大小、印刷加工為變數,探討高齡者對健康食品包裝盒之中文字視認度為本研究的目的。研究針對60歲以上的40位高齡者,進行不同的明度對比、字級大小與印刷加工之中文字視認度的實驗。選擇9筆劃數的黑色中文圓體字為實驗用字;其明度對比分低、中、高三水準;字級有9、10、11級三種;印刷加工有霧面PP上光、上光油、亮面PP上光與UV上光等四種。實驗環境照度控制在500-1000 lx之間。從研究結果得知,隨著文字與背景的明度或字體級數的增加,可降低高齡者閱讀健康食品包裝盒之中文字的錯誤次數,並提升其主觀視認度。但,在高光澤感比在低光澤感的條件下,其字級與背景明度之間的相互作用,對包裝文字的視認度有較大的影響。整體而言,為滿足高齡者較容易閱讀健康食品包裝盒文字的主觀視認度,且視認錯誤次數較低,建議低光澤的上光油印刷加工之中文圓體字大小應至少為10級,若高光澤的UV上光印刷加工之中文圓體字應至少為11級,且文字與背景需為高明度對比。
The purpose of this study is to investigate different brightness contrasts of character-background, character sizes, and surface-coating types upon the legibility of Chinese characters on health-food packages for elderly people. Forty elderly people participated in the experiment. This study grouped the health-food packages into four surface-coating types: Matte PP Coating, Varnish Coating, Poly Propylene Coating, and Ultra Violet Coating. The character sizes vary from 9Q, 10Q, and 11Q for the package print. The brightness contrasts of character-background are set to low, medium, or high levels. The Chinese characters were of the round style in black with the same stroke number of nine in this study. The experimental illumination was controlled at 500-1000 lx. Each subject read samples of health-food packages with various brightness contrasts, character sizes under a single surface-coating type. The number of misread characters and the subjective estimation were recorded during the experiment. The results of this study indicate that, the bigger the brightness contrast of character-background, and the larger the character size, the fewer the number of misread characters and the higher the subjective estimation. Furthermore, there were more significant interactions between the brightness contrast of character-background and the character size of the misreading characters for high gloss surface-coating types (such as Poly Propylene Coating and Ultra Violet Coating), than for low gloss surface-coating types (such as Matte PP Coating and Varnish Coating). Thus, for elderly people, in order to decrease the average number of misreading characters and to increase the subjective estimation, it is suggested that characters of at least size 10Q be used on Varnish Coating type surface with low gloss, and that characters of at least size 11Q be used on Ultra Violet Coating type surface with the high gloss, for Chinese characters in the round style.