Three complementary camera systems are combined to obtain a high-performance system.

Ahigh-performance digital imaging system has been assembled to provide enhanced capabilities for characterizing materials and processes. Highspeed imaging is needed for observation and analysis of such fast dynamic processes as impact fracture (including ballistically induced fracture) in advanced composite materials, dynamic deformation of materials, and hydrodynamic instabilities in jets. Because these dynamic processes occur at diverse temporal and spatial scales, there is a need for an imaging system that can operate at correspondingly diverse frame rates, spatial resolutions, and magnifications, and that is capable of recording various numbers of image frames.

A thorough market search led to the conclusion that no single commercially available electronic camera can satisfy all of the diverse requirements. Therefore, it was decided to satisfy the requirements by building the present high-performance digital imaging system as a combination of three commercially available electronic camera systems that have overlapping resolution, recording-rate, record-length, sensitivity, and other performance characteristics. The resulting assembly is a unique, state-of-the-art, ultrahighresolution/ speed imaging system for quantitative observation and analysis of dynamic processes.

High-spatial-resolution digital imaging at a rate of a million or more frames per second is needed for the analysis of many dynamic processes. Market research revealed that only rotating-mirror charge-coupled-device (CCD) camera systems can satisfy these requirements. The specific commercially available system chosen to satisfy these requirements was a Cordin Model 550 24 high-resolution rotatingmirror CCD camera system, which contains 24 cameras synchronized for imaging at a rate as high as 1.5 million frames per second. The rotating mirror and associated optics distribute incoming light to the cameras in sequence, and the exposure time and recording rate are electronically controlled in accordance with the rotation. Pictures having resolution and dynamic range superior to those recorded by use of a multichannel-plate image intensifier and having exposure times as short as hundreds of nanoseconds can be taken by use of this system.