A light source apparatus includes an airtight container having a hemispherical or semielliptical first curved portion configured to receive laser light, a hemispherical or semielliptical second curved portion opposite to the first curved portion, and a cylindrical portion connecting the first curved portion and the second curved portion; assist gas sealed in the airtight container; and a light source configured to irradiate laser light to the first curved portion from outside of the airtight container.

A light source apparatus includes an airtight container having a hemispherical or semielliptical first curved portion configured to receive laser light, a hemispherical or semielliptical second curved portion opposite to the first curved portion, and a cylindrical portion connecting the first curved portion and the second curved portion; assist gas sealed in the airtight container; and a light source configured to irradiate laser light to the first curved portion from outside of the airtight container.

A laser and methods for providing a continuous wave output beam. The laser and method includes positioning a micro-plasma chip capable of creating micro-plasmas within a resonant cavity. A gas is input into the resonant cavity and flows around the micro-plasma chip. Micro-plasmas ignite and excite the gas to create metastables. The metastables are further excited by an optical pump having an energy sufficient to cause the metastables to lase.