Accession Number : AD0845184

Title :   Synchronous Amplitude Modulation of a Multimode Ring Laser,

Corporate Author : STANFORD UNIV CA MICROWAVE LAB

Personal Author(s) : Buholz, Neal E.

Report Date : AUG 1968

Pagination or Media Count : 116

Abstract : The work is concerned with theoretical and experimental properties of a He-Ne ring laser which has internal amplitude modulation. The modulation causes the light waves to travel as two oppositely directed pulses. This scheme was conceived in order to improve the lower limit of rotation rate sensing of the ring laser by reducing the interaction between counter-rotating waves. The expected improvement would occur because the two pulses would overlap only over limited portions of the ring perimeter, and hence interactions would occur only in the neighborhood of these pulse crossing positions. To obtain counter-rotating pulses, the ring laser is operated so that numerous axial modes oscillate simultaneously, one set corresponding to each direction, and the modulator frequency is chosen to be near the axial mode interval or a multiple thereof. Certain gain and refractive effects associated with the saturation of the active medium were observed when the ring laser was operated in this manner. Explanations of these effects were obtained using a simple model of the time variation of the population inversion of the active medium. A model accounting for the presence of internal reflections was also included. The experimentally observed behavior of the system was compared to the predictions of these models. (Author)

Descriptors :   *GYROSCOPES), (*GAS LASERS, AMPLITUDE MODULATION, HELIUM, NEON, ROTATION, DETECTORS, MATHEMATICAL MODELS, GAIN, REFLECTION, THESES.

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE