Laser plasma diagnostic using ring resonators

摘要

This invention describes a system for measuring the electron number density of a plasma, which employs a laser interferometric plasma diagnostic technique and which provides significant improved time response compared to conventional laser interferometers. The method of achieving improved time response locates the plasma in one arm of a laser-excited, transmission ring resonator cavity. The response time of the interferometer is then limited only by the Q of the ring resonator cavity and is independent of the gain, the cavity Q, and the collisional lifetimes associated with the laser source.