What are the main uses of lasers?

They are used in barcode scanners, laser printers, DNA sequencing instruments, optical disk drives, optic fibre, laser surgery, skin treatments, semiconductor chip manufacturing, military devices for setting targets, measuring speed and range, etc. Apart from medical applications, lasers are also used in precision tools for cutting and moulding purposes (they can easily cut hard substances like metals and diamonds). Semiconductors lasers are also used instead of light-emitting diodes (LEDs) to activate fluorescence as a source of white light. This allows for a much smaller emitting region due to the much larger laser’s radiance and eliminates the droop experienced by LEDs. Lasers are also used in apparatus called spectrometers. Such devices help scientists to understand what different materials are made of. In the case of planetary studies, lasers are used in tools that map the surfaces of moons, planets, and asteroids. Scientists have calculated the distance between the Earth and the moon using lasers. By calculating the amount of time required for a laser ray to travel to the moon and back, astronomers can accurately predict the exact distance between the Earth and the moon.