1. 1 Graphic adapters and monitors – the summary

2. 2 Outline The summary of principles of displaying the information – adapters and monitors. Black and white monitors. Digital monitors. Analog monitors. LCD monitors and analog interface. LCD monitors and DVI interface.

3. 3 How CRT monitor is constructed? CRT – Cathode Ray Tube Controller This is the situation in black and white monitor – one electron beam. Color monitor – three electron beams.

4. 4 The image on screen – how it works? Black and white monitor (mono monitor) – just two colors are displayed. Information about color is stored in video memory as „0“ and „1“. This information is transported to monitor as analog signal. The voltage is brought to anode, the beam of electrons is either accelerated (the fluorescent layer at this dot is illuminated) or not (the fluorescent layer at this dot is not illuminated) The levels of grey color – not only two values of voltage are available, but more values. The number of analog values depends on the number of bits used to represent the information about the dot color. The digital value is converted into analog voltage which is transported to monitor and its anode.

5. 5 The image on screen – mono monitor Grapfic adapter cable monitor System bus Video memory: 0/1 (dot is illuminated/is not illuminated Cable: 0/1 voltage The consequence: the dots on monitor are illuminated/are illuminated according to the information brought from video memory Typical for text mode.

6. 6 The image on screen – mono monitor (graphics) Grapfics adapter cable monitor System bus Video memory: several bits 0/1 for each pixel analog voltage Analog voltage – it is generated in graphics adapter by converting binary representation of the pixel color (in fact level of grey color) to the analog voltage transported through the cable to monitor. With this voltage applied to anode, the beam of electrons is accelerated – different voltage – different energy with which the beam of electrons hits the fluorescent layer (pixel)on the screen – different intensity of pixel.

7. 7 The image on screen – color monitor (digital control) Graphics adapter cable monitor Video memory: 0/1 (the pixel lights/does not light), this information is available for each color R,G, B Cable: 0/1 for each color R,G,B System bus

8. 8 The image on screen – color monitor (analog control) Graphics adapter cable monitor Video memory: certain number of bits 6/8/ …. for each color R,G,B The conversion to analog voltage – for each color R, G, B one DAC is needed Cable: analog voltage for each color R,G,B System bus

9. 9 LCD monitor, DVI interface Graphics adapter cable monitor cable: 3 color components, the information is transported serially in digital form The reasons for serial interface: faster communication, wider bandwidth, higher resolution.