Specifications

Monitor Selection Criteria
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Some of NEC’s monitors use a variation on the aperture grille called the slotted mask, which is
brighter than standard shadow-mask monitors and more mechanically stable than aperture
grille–based monitors (see Figure 15.8).
Chapter 15
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Figure 15.8 Aperture-grille picture tubes (left) have their phosphors arranged in vertical stripes with one
or two reinforcing wires, depending on CRT size. NEC’s CromaClear slotted mask picture tube design (right)
provides many of the benefits of both the shadow-mask and aperture-grille designs.
The dot pitch or stripe pitch measurement is one of the most important specifications of any monitor,
but it is not the only specification. You might find the image on a monitor with a slightly higher dot
pitch superior to that of a monitor with a lower dot pitch. There is no substitute for actually looking
at images and text on the monitors you’re considering purchasing.
Image Brightness and Contrast (LCD Panels)
As previously mentioned, dot pitch is not a factor in deciding which LCD panel to purchase.
Although it’s a consideration that applies to both LCDs and CRTs, the brightness of a display is espe-
cially important in judging the quality of an LCD panel.
Although a dim CRT display is almost certainly a sign of either improper brightness control or a dying
monitor, brightness in LCD panels can vary a great deal from one model to another. Brightness for
LCD panels is measured in candelas per square meter, which is abbreviated “nt” and pronounced as a
nit. Typical ratings for good display panels are between 200 and 400 nits, but the brighter the better. A
good combination is a rating of 250 nits or higher and a contrast rating of 300:1 or higher.
Note
When you evaluate an LCD TV monitor, be sure to note the brightness settings available in computer mode and TV mode.
Many of these displays provide a brighter picture in TV mode than in computer mode.
Interlaced Versus Noninterlaced
Monitors and video adapters can support interlaced or noninterlaced resolution. In noninterlaced (con-
ventional) mode, the electron beam sweeps the screen in lines from top to bottom, one line after the
other, completing the screen in one pass. In interlaced mode, the electron beam also sweeps the screen
from top to bottom, but it does so in two passes—sweeping the odd lines first and the even lines sec-
ond. Each pass takes half the time of a full pass in noninterlaced mode. Early high-resolution moni-
tors, such as the IBM 8514/A, used interlacing to reach their maximum resolutions, but all recent and
current high-resolution (1,024×768 and higher) monitors are noninterlaced, avoiding the slow screen
response and flicker caused by interlacing.
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