METHOD OF VIEWING SUBMERGED OBJECTS AND DEVICE FOR REALISING SAID METHOD Russian patent published in 2010 - IPC G01S17/88 

FIELD: physics.

SUBSTANCE: method of viewing submerged objects involves automatically controlled scanning of submerged objects with laser radiation with a narrow beam, suppression of back-scattering interference and recording intensity of radiation reflected from different points on the surface of the object. The surface of the object is scanned pixel by pixel in two coordinates with pulse-periodic laser radiation. Back-scattering interference is suppressed through optical polarisation filtering of the useful signal and strobing the photodetector. The effect of forward scattering is further reduced during preliminary processing of the recorded reflected signal. The laser radiation source is a diode-pumped fibre-optic laser and the scanning device is in form of two mutually orthogonal acousto-optical deflectors. The output optical system is fitted with a focusing zoom lens. The reception channel in form of an input optical system has a polarisation filter, a photodetector with a strobing unit and an amplifier. A peak detector with a controlled delay device is installed behind the amplifier.

EFFECT: increased reliability, increased range of vision and improved image quality.

2 cl, 10 dwg