Hardware Reference
In-Depth Information
transistor), they produce a high-precision image. LCDs can't have the common CRT display problems
of pincushion or barrel distortion, nor do they experience convergence errors (halos around the edges
of onscreen objects).
LCD panels are less expensive to operate than CRTs because they feature lower power consumption
and much less heat buildup than CRTs. Because LCD units lack a CRT, no concerns exist about
electromagnetic VLF or ELF emissions. Although LCDs offer a comparable mean time between
failures (MTBF) to CRT displays, the major reason for LCD failures is the inverter or backlight,
which might be relatively inexpensive to replace in some models. CRT failures usually involve the
picture tube, which is the most expensive portion of the display and is often not cost-effective to
replace.
LCD panels offer a significantly smaller footprint (front-to-back dimensions), and some offer optional
wall or stand mounting. LCD panels also weigh substantially less than comparably sized CRTs. For
example, a 17-inch LCD weighs less than 10 lbs., compared to the 50 lbs. weight of 19-inch CRTs
with a similar viewing area.
LCD Monitor Selection Criteria
When selecting an LCD monitor, I recommend taking the following criteria into consideration:
• LCD monitors work best at their native resolution and can vary greatly in how they scale to
lower resolutions. Because higher resolutions result in smaller text and icons, make sure you
don't purchase a display with a higher resolution than you can easily see or use. LCD monitors
vary greatly in how well they scale from native to alternative resolutions, so you should
evaluate the panel both at its native resolution and at any other resolutions you plan to use.
• For larger displays supporting higher resolutions, using a VGA analog connection will result in
a poor quality image. In that case, you will want to use a digital connection, which means that
both the video adapter and display will need compatible digital connections such as
DisplayPort, DVI, or HDMI.
• LCDs have slower response times than most CRTs. For good performance with games, video,
and animation, look for gray-to-gray (G2G) response times of 5ms or faster.
• LCD displays have lower viewing angles than CRTs. This can be an important consideration if
you're planning to use your LCD monitor for group presentations. To improve the horizontal
viewing area, several manufacturers have developed patented improvements to the basic TFT
display, such as Hitachi's IPS, Fujitsu's multidomain vertical adjustment (MVA), and
Mitsubishi's feed forward driving (FFD)—most of which have been licensed to other leading
LCD makers. If you need wider angle viewing capability, look for LCD displays using these
technologies to achieve horizontal viewing angles of 170° or more.
• A high-contrast ratio (luminance difference between white and black) makes for sharper text
and vivid colors. Look for static contrast ratios of 1000:1 or more.
• Optional features such as integrated speakers, webcams, and USB hubs are available on many
displays.
LED Backlit Technology
Most new LCD panels use LEDs, rather than fluorescent tubes, for backlighting. By using LEDs
instead of fluorescent tubes, display warmup time is nil and mercury, a major environmental concern
when disposed of, is no longer a concern when the display is scrapped. LED backlit screens also use
