Computer Monitors - LCD and CRT
Conventional desktop monitors use Cathode Ray Tubes (CRTs).
Most laptops - and many of the newer desktop monitors - use Liquid Crystal Displays (LCDs).
Monitor Screen Resolution
Screen resolution is expressed in "picture elements" (pixels) as Width x Depth. For example, a standard MS-DOS VGA mode is 640 pixels wide by 480 deep - expressed as 640x480. Higher resolutions (more pixels on the screen) produce clearer pictures and more legible text provided:-
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the hardware can handle the greater data transfer, and |
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the operating system - or application - provides appropriate fonts for each combination of resolution, screen size, and user's visual acuity. |
CRT Monitors
CRTs have an absolute maximum resolution, but also support many lower resolutions (i.e., show fewer pixels) without compromising display quality. (For example, an LG Model SW900B, 19" CRT Monitor has a maximum resolution of 1600x1200. It also handles lower resolutions like 640x480, 800x600, 1024x768, 1152x864, and 1280x1024.)
LCD Monitors
LCDs only really support one "native" resolution. (For example, an LG Model 885LE, 18" Desktop LCD Monitor has a native resolution of 1280x1024. The DELL Inspiron 8200 N1600VT Notebook uses a 15" TFT LCD display with a native resolution of 1400x1050.)
While the native resolution is akin to the "maximum" resolution of CRTs - and the display quality at that resolution can be excellent - LCD screens have a problem running applications at lower resolutions.
Computers using LCD screens have to emulate lower resolutions in one of two ways:-
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by "Centering" a lower resolution window in the normal display. The window uses only the pixels it needs to create the lower resolution display. So, for example, an LCD screen with a native resolution of 1400x1050 pixels might show an MS-DOS VGA screen of 640x480 pixels in the middle of the display with a dark border around the centered window. The window uses only 20% of the screen area! |
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by "Expansion". The lower resolution screen is "scaled up" to the LCD's native resolution by image scaling software. The result is a "full screen" window with no wasted pixels. However, the image is slightly distorted and text clarity, in particular, reflects the difficulties all systems have in scaling fonts. |
More Information on Monitors
For more technical information on monitors - and purchasing recommendations - see:-
| ZDNet's Monitor Tech Guide |
| NEC Monitor Technology Guide |
| CNet Monitor Buying Guide |
| PCReview - LCD vs CRT Monitors |
| Geek.com's Monitor Buying Guide |