|
CRT BASIC
 |
 |
 |
| |
 |
| |
You can get a lot for your money with
CRTs, although they're often much bigger
and heavier than LCDs. In recent years,
CRT technology has advanced, so there
is very little difference in performance
among brands. In other words, unless you
buy the absolute cheapest CRT, you should
be happy with whatever you choose. Here
are some key features in CRT specifications.
|
|
Bandwidth:
The rate in megahertz (MHz) at which a CRT can
process information. As you approach the bandwidth
limit, thin black or white lines appear gray
because the electron beams cannot turn all the
way on or off fast enough to keep up. Generally,
the higher a CRT's bandwidth is, the faster
its refresh rate is at any resolution, and the
better its image quality.
Convergence: Color CRTs rely on three
separate electrical beams to project simultaneous
red, green, and blue images; these combine to
form a full-color image. If these beams are
not precisely aligned, the red, green, and blue
portions of the image may not overlap correctly;
the image will look unfocused and will have
visible colors along the edges. When the three
beams converge correctly at all points on the
display, you get a perfect image.
| Dot
pitch: A smaller dot pitch means that
a monitor can display higher-resolution
images more accurately. Some manufacturers
report the "horizontal dot pitch," which
measures only the horizontal component
of the diagonal distance between triads
and offers an easier comparison to stripe-pitch
measurements. |
|
Maximum refresh rate: If an image refreshes
too slowly on a CRT, you may notice a flicker.
You want at least 70Hz at the resolution you
intend to use. This becomes more of a factor
as the screen size gets larger, as people are
more susceptible to flicker in their peripheral
vision.
Power consumption: CRT power consumption
is typically specified in watts. A typical 19-inch
model may draw 130 watts when operating--that's
more than two standard 60-watt lightbulbs--and
will generate a good deal of heat.
Screen size: CRTs specify the diagonal
dimension of the entire picture tube. This is
one to two inches larger than the viewable image
size (also measured diagonally).
|
|
|
|
 |
 |
 |
|