Model of an underwater imaging system with a complexly modulated illumination beam

The optical transfer functions of underwater imaging systems that use narrow beams modulated by a complex high-frequency signal to form an image are studied. Images of simple objects observed with the use of such systems are calculated. The image distortions caused by the interference of modulation waves are estimated, and a method for eliminating these distortions is proposed. The potential for improving the image quality through the application of complexly modulated illumination beams is demonstrated using explicit calculations.