High-Throughput and High-Sensitivity Terahertz Scanners for Non-Destructive Evaluation of Non-Conductive Coatings and Thermal Protection Systems in Space Applications

To address NASArsquo;s need for advanced non-destructive evaluation (NDE) sensors, Lookin, Inc. proposes to develop a novel multi-pixel terahertz scanner, a transformative diagnostic tool to identify and localize visually inaccessible defects and damages in non-conductive coatings and thermal protection systems with significantly higher throughputs and over significantly larger volumes compared to what can be offered by existing NDE tools.During the Phase I SBIR program, Lookin performed feasibility studies and proved the suitability and superiority of its multi-pixel terahertz imaging systems for finding/localizing defects in materials commonly used as insulators in space applications, such as spray-on-foam insulator and cork, with a laboratory prototype multi-pixel terahertz scanner system.With the successful results obtained during the feasibility studies of the Phase I program, Lookin, Inc. proposes to extend its technological capabilities and develop a compact and portable field prototype multi-pixel terahertz scanner with enhanced resolution and scanning speed to be used for NDE of non-conductive coatings and thermal protection systems in field settings. More specifically, Lookin proposes to develop a contactless multi-pixel terahertz scanning system capable of capturing three-dimensional terahertz images of samples with a 5times;5times;15 cm3 volume at a scan rate of 10 Hz, while providing a signal-to-noise ratio of gt;60 dB and lateral/depth resolution of at least 100/10 micro;m. This terahertz imaging system is controlled by a data analysis algorithm that can create B- and C-scan images of the sample and automatically determine the position of the structural defects, such as cracks, voids, and delamination, within the samples.