視障生聽讀輔助之介面設計與使用性評估

Usability Evaluation of Assisted Screen Reader Interface for Students with Visual Impairment

設計服務的對象不侷限於一般人士，特或弱勢族群的需求滿足也是設計者所需積極思考且關注之處，有鑑於智慧手機的普及與APP軟體工具的技術日趨成熟，本研究針對視障生學習辅助的報讀語音需求，基於內建語音引擎而規畫出適合操控的互動介面，得為視障生的學習提供實質助益。實驗設計上採3x4二因子實驗，以受測者的「視覺障城」程度與語音報讀的「互動介面」模式作為自變數，前者分為：輕度、中度、重度等三種等級，後者則由：隱形區塊橫式、隱形區塊直式、常駐快捷横式、常駐快捷直式四個類別所組成，再以「使用性」作為評估指標，最後歸納出三點結論，提供介面設計之實務應用與視障學習的研究參考。1.使用性於互動介面的模式操作與操作者的視障程度間，未有明顯的交互作用存在。2.裝識學習輔助所規劃之隱形區塊類的直式與橫式介面，其使用性表現較常駐類型兩者介面方案要來得優益。3.視障程度的差異對於互動介面的使用性之影響，就輕度、中度、重度等級視障者給予的評比結果來看，其間表現並無顯著之不同產生，但隨著樣本數的多寡變化，此一差異存有顯著化之可能。

Design is served for both people without disabilities, and people with disabilities. In recent years, cellphone becomes a popular device for most people, and has the potential turning into an assisted learning tools for students with visual impairments. Hence, this study managed to develop an assisted learning interface integrated with built-in screen reader app, and a two-way ANOVA was conducted, taking ''visual impairment'' and ''interactive interface'' as independent variables. The former was divided into three level: ''moderate'', ''severe'', and ''profound'', and the latter consisted of four categories: ''invisible block with portrait orientation'', ''invisible block with landscape orientation'', ''action button with portrait orientation'', and ''action button with landscape orientation''. Furthermore, ''usability'' was used as dependent variables to evaluate the performances of interfaces. Finally, three conclusions were drawn as followed: 1. There was insignificant interaction between''visual impairment'' and ''interactive interface'' in the performance of usability. 2. The usability evaluations of ''invisible block with landscape orientation'' and ''action button with landscape orientation'' were higher than those of ''invisible block with portrait orientation'' and ''action button with portrait orientation''. 3. No significant differences in usability performances existed among visually impaired of ''moderate'', ''severe'', and ''profound''. Overall, the findings could provide a reference for further study of interface design, and enable designers to enhance the learning and interactive experiences of students with visual impairments.