Terahertz Imaging of Thin Film Layers with Matched Field Processing
Abstract
:1. Introduction
1.1. Matched Field Processing (MFP)
1.2. Applying MFP Techniques to THz Tomography
2. Methodology
2.1. Conventional THz TOF Processing
2.2. Mathematical Model for Terahertz Measurement Data
2.3. Generating THz Replica Spectra
2.4. Sample Covariance Matrix
2.5. Objective Functions
2.5.1. Bartlett Processor
2.5.2. Minimum Variance (MV) Processor
2.6. Ambiguity Surfaces
2.7. Accuracy Limitations
3. Results
3.1. Terahertz Measurement System
3.2. Layered Media Samples
3.3. Measurement Data Processing
3.4. Generating Replica Spectra
3.5. THz MFP Results for Sample A
3.6. THz MFP Results for Sample D
3.7. Error Analysis for All THz MFP Results
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
Appendix A. Propagation within Layered Media
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Sample | Manuf. Spec. (mils) | Vernier Cal. (m) |
---|---|---|
A | 30 mil | 740 |
B | 20 mil | 520 |
C | 15 mil | 390 |
D | 10 mil | 260 |
Sample | Layer | Vernier Cal. | THz MFP Bartlett | THz MFP: MV |
---|---|---|---|---|
ID | ID | (m) | (m) | (m) |
A | 740 | 750 | 750 | |
A | 60 | 70 | 70 | |
B | 520 | 510 | 510 | |
B | 60 | 70 | 70 | |
C | 390 | 380 | 370 | |
C | 60 | 60 | 70 | |
D | 260 | 250 | 240 | |
D | 60 | 60 | 60 |
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Schecklman, S.; Zurk, L.M. Terahertz Imaging of Thin Film Layers with Matched Field Processing. Sensors 2018, 18, 3547. https://doi.org/10.3390/s18103547
Schecklman S, Zurk LM. Terahertz Imaging of Thin Film Layers with Matched Field Processing. Sensors. 2018; 18(10):3547. https://doi.org/10.3390/s18103547
Chicago/Turabian StyleSchecklman, Scott, and Lisa M. Zurk. 2018. "Terahertz Imaging of Thin Film Layers with Matched Field Processing" Sensors 18, no. 10: 3547. https://doi.org/10.3390/s18103547
APA StyleSchecklman, S., & Zurk, L. M. (2018). Terahertz Imaging of Thin Film Layers with Matched Field Processing. Sensors, 18(10), 3547. https://doi.org/10.3390/s18103547