A Ruby Laser is a type of solid-state laser that uses a synthetic ruby crystal as its gain medium. It emits light in a deep red color, typically at a wavelength of 694.3 nanometers. The laser operates by exciting the ruby crystal with a flashlamp, which causes the atoms in the crystal to release energy in the form of coherent light. This process is known as stimulated emission. Ruby Lasers were among the first types of lasers developed and were invented in the early 1960s by Theodore Maiman. They are used in various applications, including laser surgery, tattoo removal, and scientific research. Their ability to produce short, intense pulses of light makes them particularly useful in these fields.