Scientists have developed many instruments that use light. Light helps man learn about his world by using the microscope and telescope. Eyeglasses use lenses and the refraction of light to help us see better. We use a camera to record faces and scenes on film in photography, movies, and television. Magnifying glass lenses focus light rays and bring them to a point to make objects appear larger.
Laser light is a special kind of beam of light.
Laser, or light amplification by stimulated emission of radiation, has light waves that are exactly the same wavelength. Its light is also very pure - it is made up of light waves of a single color. Laser beams are used in medicine to treat eye disorders in surgery, and to destroy diseased tissue. In industry laser beams can drill holes in machine parts or weld metal parts together. In the future most telephone calls may be carried by light waves traveling through optical fibers.