Abstract
Nondestructive testing using terahertz frequency electromagnetic waves is becoming increasingly popular method of inspection. Similar operating principle allows the use of inverse algorithms derived from the ultrasonic technique. In this paper algorithm and results of time reversal processing applied to pulsed terahertz inspection of dielectric objects are presented. Time reversal is implemented using finite difference time domain method. New criteria of optimal focusing time are proposed in order to estimate defects positions. Finally the algorithm is verified using the results of simulations and measurements.