FIELD: measuring technique.
SUBSTANCE: method comprises irradiating optical wave-guiding system by the single-frequency semiconductive laser, detecting transverse distribution of radiation intensity at the output of the optical wave-guiding system, determining averaged contrast of the transverse distribution of intensity of transmitted radiation, reducing contrast by reducing current of injection, measuring the time of coherence of laser radiation or width of the spectral band of the laser radiation, and determining mode dispersion from the formula proposed.
EFFECT: enhanced precision.
11 dwg
