Abstract
In recent years, the Internet has become an important part for people’s living activities. Due to the characteristic that is not restricted by time and place, the Internet also becomes a new information channel for blind and visually impaired.Blind and visually impaired use screen readers so that the information on the screen can be transformed into the auditory or tactile messages. However, lots of information could not be transformed, and as the complex structure of web pages and the image without alternative text. Therefore, blind and visually impaired might lose themselves in the Internet and decrease their willingness to use the web. Though there are many accessibility guidelines for improving the design of web pages, a lot of web pages still do not comply with and are hardly read by the blind and visually impaired.After using GOMS to analyze the screen readers that were widely used in Taiwan, it is found in this study that NVDA is better in the Internet surfing than G-mouse is. The latter is the most commonly-used screen reader for students in primary and secondary schools in Taiwan. Then a usability test is used to investigate if Internet searching using NVDA could improve the knowledge for the blind and visually impaired. In addition, Technology Acceptance model was used to find out the factors that could impact the blind and visually impaired using the Internet.The result of the usability test did not reveal significant effect of using NVDA and the Internet search for the blind and visually impaired. The reason might be that the experiment time was limited in this study. Technology Acceptance model showed that the availability was one of the important factors that could influence the blind and visually impaired on using the Internet.Therefore, the follow up study aimed to assist the blind and visually impaired to set up appropriate mental map of web site and provide the location information in a large web site. According to the mental model of the blind and visually impaired, two methods were designed: Hierarchy-size-method and Record-series-method. Then, the second usability test was conducted to evaluate the effect of the designed methods. The result showed that the blind and visually impaired could perform better as they used either method in terms of measurements of effectiveness, efficiency, and satisfaction. Less effort was needed by the users to establish the mental map of web site comparing to no method.