Transcript MONITORS - enrich your potential

MONITORS
Known as a display screens.
Monitors present visual
images of text and graphics.
Monitors vary in size, shape,
and cost.
1. Monitor’s features
The most important characteristic of a
monitor is its clarity. Clarity refers to
the quality and sharpness of the
displayed images.
i. Resolution
- One of the most important features.
- Images are formed on a monitor by
a series of dots o pixels (picture
elements).
- Resolution is expressed as a matrix
of these dots or pixels.
- For example many monitors today
have a resolution:
1280 pixel for columns
1024 pixel rows
Total = 1 310 720 pixels
- The higher a monitor’s resolution the
clearer the images produces.
ii. Dot Pitch
- The distance between each pixel.
- Most newer monitors have a dot
pitch of .31 mm or less.
- The lower the dot pitch (the shorter
the distance between pixels) the
clearer the images produced.
iii. Refresh rate
- Indicates how often a displayed image is
updated or redrawn on the monitor.
- Most monitors operate at a rate of 75HZ,
which means that the monitor is redrawn
75 times each second.
- Images displayed on monitor s with
refresh rates lower than 75 HZ appear to
flicker and can cause eye strain.
- The faster the refresh rate, the better the
quality of images displayed.
iv. Size
- Viewable size is measured by the
diagonal length of a monitor’s
viewing area.
- Common sizes are 15, 17, 19 and 21
inches.
- The smaller the monitor size the
better the quality of images
displayed.
2. How to measure the
monitor’s size
3. Types of monitor
a) Cathode-Ray tube (CRT)
-
The most common type of monitor for
the office and the home.
These monitors are typically placed
directly on the system unit or on the
desktop.
CRT’s are similar in size and technology
to televisions.
The advantages of CRT are low cost and
excellent resolution.
The disadvantages is that they are bulky
and occupy amount of space on the
desktop.
b)
Flat- Panel Monitor
- Flat-panel monitors are easier to
transport and portable monitor.
- It much thinner and require less
power to operate than CRTs.
- These monitors are widely used with
desktop, tablet PC and handheld
computer.
Types of flat-panel monitor
i. Passive matrix / dual-scan monitors
- Create images by scanning the entire screen.
- These type requires very little power, but the
clarity of the images is not as sharp.
ii. Active-matrix / thin film transistor
(TFT)
- This type do not scan down the screen,
instead each pixel is independently activated.
- They can display more colors with better
clarity.
- Active-matrix monitors are more expensive
and require more power.
c) Other monitors
These monitors are used for more
specialized applications, such as reading
books, making presentations, and
watching television.
1. E-book readers
- Handheld, book-sized devices that display
text and graphics.
- Using content downloaded from the web
or from special cartridges.
- These devices are used to read
newspapers, magazines, and entire books.
E-Book
2.
Data projectors
- Specialized devices similar to slide
projectors.
- These devices, however, connect to
microcomputers and project
computer output just as it would
appear on a monitor.
- Data projectors are commonly used
for presentations almost anywhere
from the classroom to the
boardroom.
3. High definition television
(HDTV)
- A recent development in the merger of
microcomputers and television, called
PC/TV.
- HDTV delivers a much clearer and more
detailed wide-screen picture than regular
television.
- Because the output is digital and users
can readily freeze video sequences to
create high-quality still images.
High Definition Television