Viewable Area of the Display

Two measures describe the size of your display: the aspect ratio and the screen size. Most computer displays, like most televisions, have an aspect ratio of 4:3 right now. This means that the ratio of the width of the display screen to the height is 4 to 3. The other aspect ratio in common use is 16:9. Used in cinematic film, 16:9 was not adopted when the television was developed due to the difficulty of creating a CRT that could accommodate the format. CRT manufacturing processes have greatly improved, and the aspect ratio has never been a problem with the manufacture of alternative display technologies such as LCD. In fact, with widescreen DVD movies increasing in popularity, most manufacturers now offer 16:9 displays or plan to in the near future.

The display includes a projection surface, commonly referred to as the screen. Screen sizes are normally measured in inches from one corner to the corner diagonally across from it. This diagonal measuring system actually came about because the early television manufacturers wanted to make the screen size of their TVs sound more impressive. Because the listed size is measured from the inside beveled edges of the display casing, make sure you ask what the viewable screen size is. This will usually be somewhat less than the stated screen size. Popular screen sizes are 15, 17, 19 and 21 inches. Notebook screen sizes are usually somewhat smaller, normally ranging from 12 to 15 inches. Obviously the size of the display will directly affect resolution. The same pixel resolution will be sharper on a smaller monitor and lose sharpness in larger monitors because the same number of pixels is being spread out over a larger number of inches. An image on a 21-inch monitor with a 640x480 resolution will not appear nearly as sharp as it would on a 15-inch display at 640x480.

Display's Maximum Resolution

Resolution refers to the number of individual dots of color, known as pixels, contained on a display. Resolution is typically expressed by identifying the number of pixels on the horizontal axis (rows) and the number on the vertical axis (columns), such as 640x480. The monitor's dot pitch, viewable area and refresh rate all directly affect the maximum resolution a monitor can display.