How is the screen size calculated?

The screen is measured in English inches and diagonal lines. 1 inch is equal to 2.54 cm in the metric system. For example, the diagonal length of 19 inch display is about 48 cm.

Diagonal measurement screen originated from the measurement of the first generation CRT TV screen. Most of the display tubes used at that time were round, so naturally only the diameter was needed to distinguish the size. But the image to be displayed is rectangular, so draw an inscribed rectangle on the circular display, and the diagonal of the rectangle is the diameter of the display tube.

Extended data

Screen size classification, screen size is divided into physical size and display resolution:

1, physical size refers to the actual size of the screen. The large screen must be equipped with high resolution at the same time, that is, how many pixels can be displayed in this size, and the more pixels are displayed, the greater the room for performance.

2. The screen resolution is the screen area by dividing the number of LCD units (the unit is the screen resolution obtained by dot "."). This index is the biggest factor that determines the picture quality. Therefore, when purchasing a display screen, we should not only pay attention to the color depth that the screen can display, but also the screen resolution is a very important determinant.

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