Hardware Reference
In-Depth Information
Display Specifications
A number of features and specifications differentiate one display from another. Some of
these can be confusing, and some are more important than others. The following sections
examine the features and specifications to look for when comparing or selecting displays.
Display Size
PC monitors come in various sizes, generally ranging from 15 inches to 30 inches in di-
agonal measurement. Displays smaller than 15 inches are available for specialized uses
(and are often used on smaller laptop or palmtop/netbook systems). Displays larger than
30inchesarealsoavailable;however,thesearegenerallycategorizedaslargeformatmul-
timedia displays or televisions rather than as PC monitors. In general, the larger the mon-
itor, the higher the price tag; however, there are often “sweet spots” where a certain size
may have a price advantage over smaller sizes due to sales and manufacturing popularity.
Display sizes are measured diagonally, which is an artifact from the round tubes used in
the first televisions, where the diagonal measurement was equal to the physical diameter
of the tube. Whereas the diagonal display size measures the physical size of the display,
the
viewable image size
refers to the diagonal measurement of the usable area on the
screen (for example, the OS desktop). On an LCD or LED panel, the physical diagonal
measurement and the viewable image size of the display are the same. With CRTs,
however, the viewable image size is typically 1 inch smaller than the advertised diagonal
display size. Therefore, when you're comparing LCDs or LEDs and CRTs with the same
diagonal size, the LCD or LED actually offers a larger viewable image.
Note
Many people became upset when they realized that the CRT monitors they were buying dis-
played images that were smaller than the advertised number. For example, a 17-inch CRT
monitor would display only a 16-inch-sized image. This came to a head in the mid-1990s
when several class-action lawsuits forced CRT monitor manufacturers to disclose the
view-
able image size
in the immediate proximity of the physical diagonal measurement in any
advertisements and specifications. LCDs were not affected by these lawsuits because LCDs
havealwayshadaviewableimagesizethatisthesameasthediagonaldisplaymeasurement.
Tip
Larger, higher-resolution monitors retain their value longer than most other computer com-
ponents.Althoughit'scommonforanewer,fasterprocessortocomeoutrightafteryouhave
purchased your computer or to find the same model with a bigger hard disk for the same
money,agoodmonitorcanoutlastyourcomputer.Ifyoupurchasemonitorswithlongerterm
usage considerations in mind, you can save money on your next system by reusing your ex-
isting monitor.
