about monitors,vga and svga

1. MONITORS,VGA,
SVGA

2. Monitor Overview
 The most-used output device on a
computer.
 Most desktop displays use a cathode ray
tube (CRT).
 Laptops use liquid crystal display (LCD),
light-emitting diode (LED), and gas
plasma or other image projection
technology.
 Monitors using LCD technologies are
beginning to replace CRT.

3. What is Being Used Today?
 The most popular display today
remains CRT.
 It has been available for more than 70
years.
 CRTs:
1. Vivid colors and detailed images and
text.
2. Cost less than LCD monitors.
3. Continue to evolve.

4. Monitor Specifications
 Monitor Specifications can be judged
through,
 Size
 Resolution
 Refresh rate
 Dot pitch

5. Size
 A monitor’s size affect how well we can see
images.
 With a larger monitor, we can make the objects
on the screen appear bigger.
 Monitors are measured diagonally, in inches,
across the front of the screen.
 A 17 inch monitor measures 17 inches from the
lower left to the upper right corner.
 CRT monitors viewing area is smaller than the
monitor’s overall size.

6. Resolution
 The images you see on your monitor are made
of tiny dots called pixels.
 The term resolution refers to the sharpness and
clarity of an image.
 A monitor resolution is determined by the
number of pixels on the screen. It is expressed
as a Matrix.
 The more pixels a monitor displays, higher will
be its resolution. Clearer will be images appear.

7. Quality
 Manufacturers describe quality by dot
pitch.
 Smaller dot pitches mean pixels are
closely spaced which will yield a sharper
image.
 Most monitors have dot pitches that range
from 0.22mm to 0.39mm.

8. From CRT to LCD
 CRT
 Bulky, heavy, use vacuum
tube technology.
 Using technology that was
developed in the 19th
century.
 LCD
 First LCD laptop monitors
were very small due to
manufacturing costs.
 Light, sleek, energy-
efficient, have sharp picture.

9. How Monitors Work
 Most use a cathode-ray
tube as a display device.
 CRT: Glass tube that is
narrow at one end and
opens to a flat screen at
the other end.
 Narrow end contains
electron guns.

10. Monitor Classifications
 Monochrome: Display two colors, one for
the background and one for the foreground.
 Gray-Scale: A special type of monochrome
monitor capable of displaying different
shades of gray.
 Color: Can display anywhere from 16 to
over 1 million different colors. Sometimes
called RGB monitors.

11. IBM Advances in
Display Technology
 In 1981, IBM introduced the Color Graphics
Adapter (CGA) display, able to display 4
colors and max resolution of 320x200.
 In 1984, Enhanced Graphics Adapter (EGA)
display, able to display 16 colors and
resolution of 640x350.

12. IBM Advances in Display
Technology (cont.)
 In 1987, Video Graphics Array (VGA)
display.
 Most computers today support the VGA
standard.
 In 1990, Extended Graphics Array (XGA)
display, capable of resolutions 800x600 in
true color ( 16.8 million colors) and
1024x768 in 65,536 colors.

13. 13

14. VGA
 VGA = Video Graphics Array
 Introduced by IBM in 1987, still
using today
 All points addressable
 Transmitting analog signal
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15. VGA Specifications
 256 kB Video RAM
 16-color and 256-color paletted display modes.
 Selectable 25.175 MHz or 28.322 MHz master
clock
 Maximum of 800 horizontal pixels
 Maximum of 600 lines
 Refresh rates at up to 70 Hz (Usually 60 Hz)
 Vertical blank interrupt
 Planar mode: up to 16 colors (4-bit planes)
 Packed-pixel mode: 256 colors (Mode 13h)
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16. SVGA
 Short for Super Video Graphics
Array, SVGA is a set of video standards one
step above VGA. SVGA monitors are capable
of displaying up to 16 million colors with
a resolution of 800 x 600 on 14 inch
monitors and up to a 1200 x 1600 resolution
on a 20 inch. The picture shows what the
typical VGA/SVGA connection. Today, SVGA
is being phased out by the connection
knowns as DVI.

17. SVGA
 The output of both the SVGA and VGA card is
analog; however, the internal calculations which
the card performs in orderto come to the output
voltages are all digital. There is no change
necessary to increase the number of colors an
SVGA display system can reproduce; however,
the video card must be able handle much larger
numbers, and might need to be redesigned.

18. Difference Between VGA
&SVGA
 1. SVGA is an extended version of
the VGA; VGA is now an outdated
computer display hardware which
was the standard by which the
majority of PC clone manufacturers
conformed.
 2. SVGA has an upward resolution of
1024 x 768 eight bit pixels; VGA has
a 16 color or 256 color mode .