The size of the seven-inch touch screen is 17.78 cm.
International unit calculations specify 1 inch (in) = 2.54 cm (cm), so seven inches is 7 * 2.54 cm.
Inches (吋) are units of length used in the United Kingdom (UK, the United Kingdom (Commonwealth) and its former colonies, typically 1 in = 2.54 cm, in the inch system, 12 inches for 1 foot and 36 inches for 1 yard.
The touch screen size refers to the diagonal size of the screen used. The display area of the touch screen will be smaller than the size of the touch screen area. Usually measured in inches, in inches (1 inch = 2.54 cm).
Extended data
Inch size
The origin of the code: When Emperor Henry I was in office, he personally organized the relevant personnel to discuss a yard (yard, abbreviated as yd., one foot, about 91.4 cm). How long should it be? The ministers expressed their opinions and debated. .
The British emperor, who was not bored by the side, was eager to take care of his dignity. He shot his thigh and pointed his finger at the court: stupid, one yard is the length from the tip of my nose to the tip of my index finger. The code is just like this.
The origin of feet: feet (abbreviated as ft. equals 12 inches, 1/3 yards, 0.3048 m) in English means "foot". In fact, one foot is the length of one adult man's foot. Since the length of the foot varies from person to person, it is necessary to specify a standard foot length when using it.
In the 16th century, the Germans solved this problem in a very simple way. On a Sunday, they let the 16 men coming out of the church stand together, then add the length of their left foot together and divide by 16, to find an average foot length. This is the foot that is used now.
The origin of inches: inches (inch, abbreviated as in.) The original meaning in Dutch is the thumb, one inch is the length of a thumb. Of course, the length of the person's thumb is also different.
In the 14th century, Emperor Edward II promulgated the "standard legal inch." The rule is that the three largest pieces of wheat are selected from the middle of the barley ears and are lined up one inch in length.
Reference source: Baidu Encyclopedia - size
