A dot-matrix display is a display device used to display information on machines, clocks, railway departure indicators and many other devices requiring a simple display device of limited resolution.
The display consists of a dot matrix of lights or mechanical indicators arranged in a rectangular configuration (other shapes are also possible, although not common) such that by switching on or off selected lights, text or graphics can be displayed. A dot matrix controller converts instructions from a processor into signals which turns on or off lights in the matrix so that the required display is produced.
Pixel resolutions
Common sizes of dot matrix displays:
- 128Ã16 (Two lined)
- 128Ã32 (Four lined)
- 128Ã64 (Eight lined)
Other sizes include:
- 92Ã31 (Four or three lined)
Character resolutions
- A common size for a character is 5Ã7 pixels, either separated with blank lines with no dots (in most text-only displays), or with lines of blank pixels (making the real size 6x8). This is seen on most graphic calculators, such as Casio calculators or TI-82 and superior.
- A smaller size is 3Ã5 (or 4Ã6 when separated with blank pixels). This is seen on the TI-80 calculator as a "pure", fixed-size 3Ã5 font, or on most 7Ã5 calculators as a proportional (1Ã5 to 5Ã5) font. The disadvantage of the 7Ã5 matrix and smaller is that lower case characters with descenders are not practical. A matrix of 11Ã9 is often used to give far superior resolution.
- Dot matrix displays of sufficient resolution can be programmed to emulate the customary seven-segment numeral patterns.
- A larger size is 5Ã9 pixels, which is used on many Natural Display calculators.
See also
- Display examples
- Flip-disc display
- Fourteen-segment display
- Hitachi HD44780 LCD controller
- LED panel
- Sixteen-segment display