THERMAL-OPTICAL METHOD OF EXAMINATION OF UNDERWATER OBJECT Russian patent published in 2002 - IPC

FIELD: underwater acoustics, detection and examination of noiseless or low-noise underwater objects in full-scale pond. SUBSTANCE: according to proposed method examined underwater object is irradiated with laser beam in the form of train of laser pulses heating surface of object. Point of irradiation in this case turns to be source of sound waves received by directional sonar receiver. Novelty of method lies in scanning of laser beam over surface of object with speed of sound. This approach makes it possible to obtain signal of increased amplitude across input of sonar receiver thanks to effect of accumulated rise of acoustic pressure which occurs owing to fact that laser beam accompanies scanning light pulse and feeds it with energy uninterruptedly. EFFECT: possibility of scanning of laser beam over surface of object with speed of sound. 2 cl, 3 dwg