Terminals which offer a full display of text on a visual display unit should allow adjustment of the size of the characters. The characters must also be of good proportions with clear character shapes. There must also be a strong contrast between the characters and the background. For some visual impairments it is also helpful to be able to reverse the text from dark on a light background to light characters on a dark background. The display screen should be capable of positional adjustment to avoid any reflected light.
Telephone features that make a difference .