Graphic adapters and monitors

1
Graphic adapters and monitors the summary
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
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
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
The image on screen mono monitor
Cable 0/1 voltage
Grapfic adapter
monitor
cable
Video memory 0/1 (dot is illuminated/is not
illuminated
The consequence the dots on monitor are
illuminated/are illuminated according to the
information brought from video memory Typical
for text mode.
System bus
6
The image on screen mono monitor (graphics)
analog voltage
Grapfics adapter
monitor
cable
Video memory several bits 0/1 for each pixel
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.
System bus
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
The image on screen color monitor (digital
control)
Cable 0/1 for each color R,G,B
Graphics adapter
monitor
cable
Video memory 0/1 (the pixel lights/does not
light), this information is available for each
color R,G, B
System bus
8
The image on screen color monitor (analog
control)
System bus
Cable analog voltage for each color R,G,B
Graphics adapter
monitor
cable
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
9
LCD monitor, DVI interface
cable 3 color components, the information is
transported serially in digital form
Graphics adapter
monitor
cable
The reasons for serial interface faster
communication, wider bandwidth, higher
resolution.