Parallel processing of ultrasonic signals in a single photorefractive crystal

During the last years, we have developed a photorefractive ultrasonic sensor. This sensor is used for non-destructive testing of materials and parts. It works with one measurement point and the laser beam scans the surface of the object to characterize. One possibility to increase the evaluation speed is to develop a multichannel sensor. We will present the experimental implementation and characterization of such a sensor that simply derives from the single point sensor due to principle of holography, by the simple use of a line or matrix of detectors.