Ruby Laser

This model illustrates one type of laser, specifically a **ruby laser**, which is a solid-state laser that uses a ruby crystal as its laser medium. The ruby laser is notable for being one of the few solid-state lasers capable of producing visible light. The key components of a ruby laser include the laser medium (ruby), the pump source, and the optical resonator. In a ruby laser, a flash tube (a gas discharge tube) serves as the energy source or pump source. The flash tube supplies energy to the laser medium, causing the electrons in the lower energy states of the ruby crystal to absorb this energy and move to an excited state. The ruby rod, which is cylindrical in shape, is positioned between two mirrors. One mirror is fully silvered, reflecting all the light, while the other is partially silvered, reflecting most of the light but allowing a small portion to pass through as the output laser beam. The light generated within the ruby laser medium bounces between the two mirrors, stimulating additional electrons to return to their ground state by emitting light. This process is known as stimulated emission and is responsible for producing the laser beam.