Guidelines for characteristics of output devices. ▇▇▇▇ et al. (2004) mention the following guidelines for output devices designers: Select the output device with the higher contrast between characters and background. For example, choosing between an LCD and CRT, an important consideration is to select based on best contrast ratio for the ambient light conditions. A 4-letter word this approximates the width of your thumb at arm’s length. Keep visual output screens adequately shielded from glare. Provide an adaptive (adjustable) display when feasible and provide instruction to the user about how to change screen resolution. Consider advising an older user to set the resolution of their computer display to 800 x 600 pixels or lower (640 x 480 pixels) to enhance access to small icons typical in today’s software interfaces. Use built-in controls (e.g., Microsoft Windows accessibility functions available through Control Panel settings) or special purpose software. Permit adjustability of output intensity and frequency of sounds. For important visual warning messages, repetitively flash the information rather than have it come on and stay on. However, make sure that the flashing is not so fast as to impede reading of the message. Prefer tactile output devices for simple signalling (e.g., using moderate to high frequency vibration ~250 Hz) when auditory and visual output would be difficult to process (noisy environments, glare situations) or would be disruptive to performance of the user or nearby personnel. For important auditory warnings, select output (e.g., speaker) systems that emit sounds in the 500- 1000 Hz frequency range and repeat the message until acknowledged. Older users are easily distracted by extraneous design detail or background noise. That is why graphics need to be carefully selected for relevance rather than decoration. Multi-media approaches and the more flamboyant Web pages may disadvantage older users. (▇▇▇▇ et al, 2004).
Appears in 1 contract
Sources: Ethics and Data Protection Framework
Guidelines for characteristics of output devices. ▇▇▇▇ et al. (2004) mention the following guidelines for output devices designers: Select the output device with the higher contrast between characters and background. For example, choosing between an LCD and CRT, an important consideration is to select based on best contrast ratio for the ambient light conditions. A 4-letter word this approximates the width of your thumb at arm’s length. Keep visual output screens adequately shielded from glare. Provide an adaptive (adjustable) display when feasible and provide instruction to the user about how to change screen resolution. Consider advising an older user to set the resolution of their computer display to 800 x 600 pixels or lower (640 x 480 pixels) to enhance access to small icons typical in today’s software interfaces. Use built-in controls (e.g., Microsoft Windows accessibility functions available through Control Panel settings) or special purpose software. Permit adjustability of output intensity and frequency of sounds. For important visual warning messages, repetitively flash the information rather than have it come on and stay on. However, make sure that the flashing is not so fast as to impede reading of the message. Prefer tactile output devices for simple signalling (e.g., using moderate to high frequency vibration ~250 Hz) when auditory and visual output would be difficult to process (noisy environments, glare situations) or would be disruptive to performance of the user or nearby personnel. For important auditory warnings, select output (e.g., speaker) systems that emit sounds in the 500- 500-1000 Hz frequency range and repeat the message until acknowledged. Older users are easily distracted by extraneous design detail or background noise. That is why graphics need to be carefully selected for relevance rather than decoration. Multi-media approaches and the more flamboyant Web pages may disadvantage older users. (▇▇▇▇ et al, 2004).
Appears in 1 contract
Sources: Ethics and Data Protection Framework