5.6.2 Arrangement of Visual Information
5.6.2.1 Screen Organization
A standard display screen organization should be evident for the location of various system functions (such as a data display zone, control zone, message zone) from one display to another.
5.6.2.2 Grouping of Information in a Display
Information on a display should be grouped according to obvious principles, e.g., by task, system, function, sequence, etc., based upon the user's requirements in performance of the ongoing task.
5.6.2.3 Demarcation of Groups
Information groups should be visually distinct, e.g., separated by blanks, lines, color coding, or other means.
5.6.2.4 Consistent Presentation
The arrangement and presentation of identical visual information should be consistent from application to application.
5.6.3 Visual Display Units (VDU)
5.6.3.1 Night Display
All information should be presented emitting as little light as possible at night. The displays should be designed to show a light text on a dark non-reflecting background at night.
5.6.3.2 Day and Night Legibility
Displays should be capable of being read day and night.
5.6.3.3 Background Color
A single neutral background color should be used that has a hue which allows the information (foreground) to be easily visible and which does not distort or interfere with the coding aspects of the display.
5.6.3.4 VDU Resolution
The display should have adequate resolution; i.e., users can discriminate all display elements and codes from the maximum intended viewing distance.
5.6.3.5 VDU Contrast
The contrast ratio of the display should be greater than 3:1 and less than 15:1; a contrast ratio of 7:1 is preferred.
5.6.3.6 Background Luminance
A background luminance level of 15 cd/m2 to 20 cd/m2 should be used at daylight.
5.6.3.7 Display Luminance
The display luminance should be between 80 cd/m2 to 160 cd/m2 at daylight
5.6.3.8 Flicker
The display should be "flicker free"; the refresh rate should have a minimum of 65 Hz.
5.6.3.9 Image Continuity
The display should maintain the illusion of a continuous image, i,e., users should not be able to resolve scan lines or matrix spots.
