Y
ou need to measure length accurately to do things like make a dress, build a house, survey a plot of land, or determine if the home team made a first down on the football field. These length measurements and many others are often made with the help of a measuring tape. The major companies that produce the tape measures we use in everyday life rely on waves of light as the ultimate ruler to ensure their tapes are accurate.

Some manufacturers use highly accurate reference tape measures to print their familiar hash marks on the tape. Some are printed using computer-controlled ink printers with tiny print heads to ensure the markings are laid down accurately.

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