Producing bowtie limited diffraction beams with synthetic array experiment

A synthetic array experiment has been used to produce bowtie limited diffraction beams in water, which are in close conformity to those obtained from theory and computer simulations. A broad-band PZT ceramic/polymer composite transducer of one mm diameter is scanned in a raster format and placed at the center of elements of an equivalent two-dimensional array of 50 mm diameter aperture. A polyvinylidene fluoride needle hydrophone of 0.5 mm diameter receives the waves generated by the transducer. A depth of field of 216 mm is achieved for these bowtie beams, along with low sidelobes.