In this paper, Fourier methods are used to obtain an efficient tomographical technique from which non-destructive evaluation of composite materials may be possible. A new ultrasonic scanning method is developed, that combines 3rd and 4th generation scanning methods. HIGH-frequency polymer transducers, up to 50 MHz, are used to measure fan-beam projections of time-of-flight and attenuation. Data from scanning of special polyurethane "phantoms", manufactured for simulation of complicated composite structures, has been applied for evaluation of small refractive index variations. Examination with ultrasonic through- transmission scanning equipment is used to verify the applicability of fan-beams for non-destructive applications, in particular the study of defects in materials. The measurements are finally compared to simulations of the artificial shaped composite material.