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When shopping for a new
computer system, we tend
to fret over such things as the
CPU speed or
hard disk size, but what
about the one component of your system that is used just as much? Of course
we're talking about the monitor.
Often referred to as a
display screen,
a video display terminal (VDT) or visual display unit (VDU), the monitor is the component of your computer system
that displays the messages and data being processed and utilized by the
computer's CPU.
The two types of monitor
technologies available to consumers are available in
CRT monitors and
LCD monitors. There are big differences
between LCD and CRT, and while LCD technology has advanced to the point
where its viewing quality is comparable to CRTs, many people today still choose
to purchase a CRT monitor. CRTs are bigger and bulkier than an LCD, they
consume more power and are prone to
screen flicker. LCD monitors, however, are more expensive when compared to CRTs, they introduce the problem of viewing angles, and
generally have less accurate color replication.
Each type of monitor, as you
can see, has its advantages and disadvantage. In this article we will provide a
comparison of CRT and LCD monitors, along with defining
some of the many specifications and terminology you should be aware as you decide between an LCD and CRT monitor.
CRT Monitors
Sort for cathode-ray
tubes,
CRT monitors were the only choice
consumers had for monitor technology for many years.
Cathode ray tube (CRT)
technology has been in use for more than 100 years, and is found in most
televisions and computer monitors. A CRT works by moving an electron beam back
and forth across the back of the screen. Each time the beam makes a pass across
the screen, it lights up phosphor
dots on the inside of the
glass tube, thereby illuminating the
active portions of the
screen. By drawing many such lines from the top to the bottom of the screen, it
creates an entire screen of images.
LCD/Flat panel Monitors
Short for liquid crystal display, LCD technology can
be found in digital watches and computer monitors. LCD displays use two
sheets of polarizing material with a liquid crystal solution between them. An
electric current passed through the liquid causes the crystals to align so that
light cannot pass through them. Each crystal, therefore, is like a shutter,
either allowing light to pass through or blocking the light. Color LCD displays
use two basic techniques for producing color: Passive matrix is the less
expensive of the two technologies. The other technology, called
thin film transistor
(TFT) or
active-matrix, produces color images that are as sharp as traditional
CRT displays, but the
technology is expensive.
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Key Terms To
Understanding Monitors
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CRT vs. LCD - The Pros and Cons of Each
Resolution & Viewing Quality
Resolution on
a CRT is flexible and a newer model will provide you with viewing
resolutions of up to
1600 by 1200 and higher, whereas on an LCD
the resolution is fixed within each monitor (called a native resolution).
The resolution on an LCD can be changed, but if you're running it at a
resolution other than its native resolution you will notice a drop in
performance or quality.
Both types of monitors (newer models) provide
bright and vibrant color display. However, LCDs cannot display the maximum
color range that a CRT can. In terms of image sharpness, when an LCD is
running at its native resolution the picture quality is perfectly sharp. On
a CRT the sharpness of the picture can be blemished by soft edges or a
flawed focus.
A CRT monitor can be viewed from almost any
angle, but with an LCD this is often a problem. When you use an LCD, your
view changes as you move different angles and distances away from the
monitor. At some odd angles, you may notice the picture fade, and possibly
look as if it will disappear from view.
Refresh Rate
Some users of a CRT may notice a bit of an annoying flicker, which is an
inherent trait based on a CRTs physical components. Today's graphics cards,
however, can provide a high
refresh rate
signal to the CRT to get rid of this otherwise annoying problem. LCDs are
flicker-free and as such the refresh rate isn't an important issue with LCDs.
Dot Pitch
Dot pitch
refers to the space between the
pixels that make
up the images on your screen, and is measured in millimeters. The less space
between pixels, the better the image quality. On either type of monitor,
smaller dot pitch is better and you're going to want to look at something in
the 0.26 mm dot pitch or smaller range.
Screen (viewable) Size
Most people today tend to look at a 17-inch CRT or bigger monitor. When you
purchase a 17-inch CRT monitor, you usually get 16.1 inches or a bit more of actual
viewing area, depending on the brand and manufacturer of a specific CRT. The
difference between the "monitor size" and the "view area" is due to the
large bulky frame of a CRT. If you purchase a 17" LCD monitor, you actually
get a full 17" viewable area, or very close to a 17".
Physical Size
There is no denying that an LCD wins in terms of its physical size and
the space it needs. CRT monitors are big, bulky and heavy. They are not a
good choice if you're working with limited desk space, or need to move the
monitor around (for some odd reason) between computers. An LCD on the other
hand is small, compact and lightweight. LCDs are thin, take up far less
space and are easy to move around. An average 17-inch CRT monitor could be
upwards of 40 pounds, while a 17&-inch LCD would weigh in at around 15 pounds.
Price
As an individual one-time purchase an LCD monitor is going to be more
expensive. Throughout a lifetime, however, LCDs are cheaper as they are known
to have a longer lifespan and also a lower power consumption. The cost of
both technologies have come down over the past few years, and LCDs are
reaching a point where smaller monitors are within many consumers' price
range. You will pay more for a 17" LCD compared to a 17" CRT, but since the
CRT's actual viewing size is smaller, it does bring the question of price
back into proportion. Today, fewer CRT monitors are manufactured as the
price on LCDs lowers and they become mainstream.
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DID YOU KNOW...
In March 2009 Hitachi
Displays plead guilty to LCD price fixing joining LG Display,
Chunghwa Picture Tubes (CPT) and Sharp. Hitachi will pay US$31
million in fines for its role in fixing LCD prices sold to Dell
for LCD monitor and notebook PC applications according to the US
Department of Justice.
[Source:
Display Blog] |
Based in Nova Scotia, Vangie Beal is has been
writing about technology for more than a decade. She is a frequent
contributor to
EcommerceGuide and
managing editor at
Webopedia. You can
tweet her online @AuroraGG
Last updated August 28, 2009
The Principles of
LCD Technology
In this selection everything from the properties of liquid crystal molecules to
the basic principle of display technology is explained.
Understanding CRT Monitor Specifications
From About.com, this article explains what to Look for When Buying a CRT
Monitor.
WorkstationPlanet:
Display
Decisions: LCD or CRT?
Flat Panels Rule Workstation users don't care much about aesthetics, so the fact
that LCDs are prettier and take up less desk space than CRTs does not impress
them. Falling prices and increased performance, however, are making LCD panels
increasingly popular among workstation users.
HardwareCentral:
LCD Monitors Go Mainstream
While flat-panel monitors have been on the market for years -- originally
adopted by Wall Street traders who wanted to squeeze multiple screens onto small
desks -- recent technology and production enhancements, along with
commensurately lower prices, have made them an increasingly attractive option
for many businesses.
Webopedia Guides
Use this Guide section to find articles,
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ERGO In
Demand
Follow the steps in this guide to learn how to use your monitor ergonomically
Small Business Computing:
Samsung SyncMaster 192N Review
If longing looks, comments, and inquiries from fellow workers walking past the
Labs, Weather, & Sports Desk are any indication, Samsung has a winner in its new
SyncMaster 192N.
Webopedia's Did You Know...
Find out all about Northern vs. Southern Hemisphere Monitors |
