Visual Display Flashcards
three basic types of visual displays
- check display
- qualitative display
- quantitative display
indicates whether or not a given condition exists (for example a green light indicates normal function)
check display
indicates the status of a changing variable or its approximate value, or its trend of change (for example, a pointer moves within a “normal” range).
qualitative display
shows exact information that must be ascertained (for example, to find a location on a map, to read text or to draw on a computer monitor), or it may indicate an exact numerical value that must be read by the operator (for example, a time or a temperature).
quantitative display
Design guidelines for visual displays
Arrange displays, Group displays, Make sure that all displays are properly illuminated or illuminant, coded and labelled according to their function, Use lights, often coloured, to indicate the status of a system (such as ON or OFF) or to alert the operator that the system, or a subsystem, is inoperative and that special action must be taken.
indicates an emergency condition that requires immediate action
flashing red light
four different kinds of displays are traditionally used
- moving pointer (with fixed scale)
- moving scale (with fixed pointer)
- counters
- “pictorial” displays
should be simple and uncluttered, with graduation and numbering so designed that correct readings can be taken quickly
scale
should be located outside the scale markings so that they are not obscured by the pointer
Numericals
should end with its tip directly at the marking
pointer
when did mechanical displays with pointers and printed scales were increasingly replaced by “electronic” displays with computer-generated images, or solid-state devices using light-emitting diodes
1980s
The displayed information may be coded by
shapes
alphanumeric
figures, pictures,illustration
shades of black, grey
colours
One measure used to assess the image
quality is the …
modulation transfer function (MTF)
. It describes the resolution of
the display using a special sine-wave test signal;
MTF
have only one colour, usually either green, yellow, amber, orange or white (achromatic)
Monochrome displays
T or F. No more than 7 colours should be used in displays
True
Cannot be combined with red:
Blues and Cyans
Suggested to combine with green, yellow, white:
-orange, red
-blue, cyan
-cyan, orange
Cannot be combined with Blues:
Magenta
is a good colour for backgrounds and large shapes. However, should not be used for text, thin lines or small shapes.
Blue
The colour of alphanumeric characters should not contrast with that of the background
False
makes the display much more acceptable for users who have colour-vision deficiencies
Redundant coding
Red and ___ should not be used for small symbols and small shapes in peripheral areas of
large displays.
Green
TorF. Using opponent colours (red and green, yellow and blue) adjacent to one another or in an
object/background relationship is sometimes beneficial and sometimes detrimental.
True
