In the design of optical antenna of Fourier transform laser warning receiver

the research on spatial coherence of laser from the multimode fiber optical antenna is important.A light source model regarding the fiber as a secondary source was established based on optical field distribution analysis.The laser spatial coherence from the fiber was analyzed by means of the Young′s double-slit interference experiment and statistical theory.The mutual intensity of laser emitted from the fiber was deduced

and then the mathematical formula of spatial coherence was obtained.The experiments demonstrate the validity of the theoretical analysis.