本研究以視障者操作使用性之觀點,從觀察視障者在操作盲用電腦與即時通訊軟體的過程中,其操作介面使用性不同於一般明眼人。因此,將探討介面選單種類之設計與操作使用性之相關性,並經由實驗、主觀滿意度量表及半結構式訪談,得知時間績效、錯誤率及滿意度,推論出視障者在操作即時通訊的介面選單之設計需求。為達此研究目的,先經由前導研究問卷調查得知MSN和Skype二款即時通訊軟體為視障者最常使用,並將二款即時通訊軟體做為後續的實驗樣本,且以視障者最常使用之四項介面功能設定實驗任務,將12位全盲受測者分為有上課學習經驗和沒有上課學習經驗的各6位。 結果得知,視障者在操作Skype的時間績效高於MSN,而在學習滿意度方向,MSN的學習操作易於Skype,推論Skype的介面選單設計多使用到系統功能選單,且會使用快選功能鍵多為有上課學習經驗者,對於一般沒有學習經驗之視障者在操作使用較為不易。建議在介面選單之設計須注意:1.在主視窗及主要介面功能選單種類以單一選單設計。2.介面功能的單一項目數為多時,以階層式選單設計。3.常使用之介面功能,可增加具系統功能選單設計。4.系統功能選單的操作使用,需容易且不需特別學習即可使用。
This usability research focuses on the Instant messenger (IM) clients with visual disabilities. The navigating interfaces used in our observation are specially opted for the blind people. With the assumption that the interface is a critical factor that affects user performance in terms of efficiency and error rate, this research provides an interface design guideline based on data obtained from a laboratory observation of blind and/or visually impaired users navigating through IM. MSN and Skype™ are under our special observation because, prior to this study, our survey shows that, among people with visual disabilities, MSN and Skype™ are the 2 most popular IM applications. In this experiment, four interface functions are chosen as independent variables, 6 experienced and 6 inexperienced fully blind users are interviewed. The result shows that Skype™ scores much higher than MSN in term of user performance effectiveness; however, on the other aspect of learning satisfaction, MSN is much easy to use than Skype™. It might be assumed that the user interface of Skype™ is not easier to inexperienced fully blind users because of too many system function keys. Here are some of our suggestions for IM client design: 1. Use single selection menu for the major window/ interface. 2. Use Hierarchical menu design for multiple menu-items in layers for sub window/interface. 3. Use Event-trapping menu design for arrange the most frequent used function buttons on the first/last. 4. Make menu wording user friendly, simple, clear, and readily understandable.