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If you've come here
looking for a detailed technical analysis of the various
types of computer monitors, you've come to the wrong
place. In the long ALK tradition (hey, four months is a
long time in the computer industry), this article
discusses the basics of monitor buying for the normal,
sane user. If you stretch a point, it might be adequate
for a proto-geek. If you are a commercial artist who
actually understands things like hue, luminance and color
temperature, you should flee the room immediately.
That being said, here are
the main things we're going to worry about: display
sharpness (dot pitch), screen size and resolution. We'll
look at some of the other issues like refresh rates,
controls and preset modes, too, but only after we've
dealt with the "big three" basics.Dotting Your Eyes
Ultimately, the image on your monitor is made up of
(brief pause to calculate) about a zillion tiny dots. The
smaller and more tightly spaced the dots, the sharper the
picture. (No, we are not talking about pixels, that comes
later. Sit down.) Computer monitors have a lot of tiny
dots, televisions have, relatively speaking, a few big
blobby dots. The size and spacing of these dots is
expressed by a value called dot pitch. Just
about any decent monitor will have a dot pitch of .28 mm
or better. Some of the pricier ones will be down around
.25 mm (i.e., smaller numbers are better). Don't bother
buying anything that has a dot pitch coarser than .28 mm.
Can You See Me?
It doesn't matter if the screen is nice and sharp if it's
not big enough for you to see what you are doing. Monitor
size is specified by the diagonal distance from one
corner of the screen to the other. Since the ratio of
width to height is always about 4:3, you only need the
one number. Naturally, the computer industry chooses the
largest one. The smallest, usable size is 14 inches; a
15-inch monitor is better if you can affford a little
extra money. After that, things begin to get expensive.
Choosing the right size
monitor is a function of your budget, your eyesight and
your display resolution requirements. The
computer builds up the various things it displays on the
screen on a grid of picture elements or pixels.
A pixel is a sort of standardized dot used to paint
images. For example, the default resolution used by
Windows is 640x480 -- 640 pixels across by 480 down. This
is also the maximum "comfortable" resolution
for 14-inch monitors although 800x600 is usable if you've
got good eyes and/or an exceptional monitor. If you're
really desperate for screen real estate, you can squeeze
in 1024x768 pixels, but that's the limit for most 14-inch
units and it's not much fun to look at.
Herewith, the ALK handy,
opinionated, official list of comfortable/usable
resolutions for the various common monitor sizes for
people with normal eyesight:
14-inch: 640x480/800x600
15-inch: 800x600/1024x768
17-inch: 1024x768/1280x1024
20/21-inch:
1024x768/1280x1024
One more little point here: just because a monitor has,
say, a 15-inch tube doesn't mean you get a 15-inch
diagonal display area. In fact, the viewable area
will certainly be a bit less. If it's a lot less, you
might wish to spend your money elsewhere. It's really
best to look at a monitor before you buy it. If you can't
do that, at least try to pry the viewable area
specification out of the salesperson before you decide
which brand or model to purchase.
Decisions,
Decisions...
So, your primary consideration is probably going to be
based on how much screen real estate you need. For what
it's worth, I find a resolution of 640x480 to be barely
adequate. It's just not a big enough window on the world.
If you plan to do any serious word processing or
spreadsheet work or web surfing, 640x480 is a real
nuisance. Going to 800x600 increases your elbow room by
better than 50% and is the lowest really useful screen
resolution. In other words, this is a long-winded way of
recommending that you buy at least a 15-inch monitor,
unless you are on a really tight budget. Bigger is
better.
Embellishments
OK, once you've dealt with "how big", there are
some other, secondary issues to consider. None of these
are quite as important as size, dot pitch and resolution,
but they aren't chopped liver, either.
Energy saving features - Just about any new
monitor will have features that reduce its energy
consumption if your computer supports them.
Typically, these monitors will drop down to less
power-hungry settings if they stand unused for a period
of time.
Reduced emissions - Almost all modern computer
monitors meet something called the SWEDAC MPRII reduced
emissions guidelines. It's never been conclusively proved
that "radiation" from monitors causes health
problems, but enough countries adopted this standard that
the manufacturers fell into line. This also had one
unintended, but beneficial, consequence: Old monitors
build up a pretty good static charge on the surface of
the screen, making them big-time dust magnets. New ones
don't need to be cleaned as often.
Digital vs. analog - A few of the lower-end
monitors have analog controls, the rest are digital. How
do you tell? Well, basically, if the controls look like a
series of little volume-control wheels, it's probably
analog; if everything is set with buttons, it's digital.
Digitally controlled monitors offer better, more precise
control over display dimensions and color parameters.
They also incorporate preset modes for the more
common screen resolutions. This keeps the display area
from shifting around on the screen when you switch
between different resolutions -- a real nuisance on early
monitors.
Refresh rates - Monitors actually repaint the
display many times per second. As a general rule, the
higher the refresh rate at a given resolution,
the better it looks. Refresh rate capabilities go up with
price and size.
Interlaced vs. non-interlaced - Old, obsolete
monitors used a technique called interlacing to handle
high resolutions. This shouldn't be an issue these days.
If the monitor is not non-interlaced, don't buy
it.
Flat screens - Your display will look better if
the screen has less curvature. Most up-to-date monitors
have "pretty flat" screens. A few of the really
pricey ones do better.
Plug & Play - Plug & Play is really a
Windows 95 thing right now. It's getting to be a fairly
common feature on new monitors and it's pretty handy. It
lets the operating system query your monitor and
automatically make the proper arrangements for resolution
and refresh rate settings.
Focus
As with any piece of computer gear, the real key is to
focus on the essentials. When it comes to monitors, this
means getting a reasonably sharp display (.28 dot pitch
or better) and choosing a screen size large enough to
handle your desired resolution comfortably. Within these
parameters, buy the best you can afford. And, if
possible, go to a store and actually look at the darn
thing before you buy it.
Reference
Yahoo maintains a fairly extensive collection of links to
information about monitors. Here's a good place to start:
Yahoo! - Business and
Economy-Companies-Computers-Peripherals-Monitors
Many thanks are due to the following
"beta testers" who provided many useful
suggestions and a much needed sanity check:
Greg
Chapman David
Freeman Sandy
Garrett Neil Krandall
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