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Journal of the Optical Society of America B

Journal of the Optical Society of America B


  • Vol. 21, Iss. 6 — Jun. 1, 2004
  • pp: 1178–1191

Quasi-optic synthetic phased-array terahertz imaging

John O'Hara and D. Grischkowsky  »View Author Affiliations

JOSA B, Vol. 21, Issue 6, pp. 1178-1191 (2004)

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A quasi-optic terahertz (THz) imaging system that utilizes optoelectronic methods for pulsed THz generation and reception and optical methods for image formation is demonstrated and theoretically explained. The system can be used to produce coherent, field amplitude, and energy density images with diffraction-limited resolution in two transverse dimensions. Simultaneous bandwidth-limited resolution is achieved in the depth dimension by means of the ranging capabilities of the system. The system is shown to accurately produce images of several objects to verify diffraction-limited imaging. Imaging power is extended by aperture synthesis to result in transverse resolution the order of a wavelength. Several individual, coherent images are recorded, each synthetically appearing to be formed by a different element of an optical phased array. The multiple images are simply superposed to create a higher-resolution image. Theoretical calculations fully describe the broadband imaging and include aberration and diffraction effects to further verify system performance. Calculated images are a good match with experimental results.

© 2004 Optical Society of America

OCIS Codes
(110.5100) Imaging systems : Phased-array imaging systems
(250.0250) Optoelectronics : Optoelectronics
(320.0320) Ultrafast optics : Ultrafast optics

John O'Hara and D. Grischkowsky, "Quasi-optic synthetic phased-array terahertz imaging," J. Opt. Soc. Am. B 21, 1178-1191 (2004)

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  1. D. H. Auston, K. P. Cheung, and P. R. Smith, “Picosecond photoconducting Hertzian dipoles,” Appl. Phys. Lett. 45, 284–286 (1984).
  2. M. B. Ketchen, D. Grischkowsky, T. C. Chen, C.-C. Chi, I. N. Duling III, N. J. Halas, J.-M. Halbout, J. A. Kash, and G. P. Li, “Generation of subpicosecond electrical pulses on coplanar transmission lines,” Appl. Phys. Lett. 48, 751–753 (1986).
  3. B. B. Hu, X.-C. Zhang, D. H. Auston, and P. R. Smith, “Free-space radiation from electro-optic crystals,” Appl. Phys. Lett. 56, 506–508 (1990).
  4. Q. Wu and X.-C. Zhang, “Free-space electro-optic sampling of terahertz beams,” Appl. Phys. Lett. 67, 3523–3525 (1995).
  5. M. van Exter and D. R. Grischkowsky, “Characterization of an optoelectronic terahertz beam system,” IEEE Trans. Microwave Theory Tech. 38, 1684–1691 (1990).
  6. K. McClatchey, M. T. Reiten, and R. A. Cheville, “Time resolved synthetic aperture terahertz impulse imaging,” Appl. Phys. Lett. 79, 4485–4487 (2001).
  7. J. O’Hara and D. Grischkowsky, “Synthetic phased-array terahertz imaging,” Opt. Lett. 27, 1070–1072 (2002).
  8. L. Thrane, R. H. Jacobsen, P. Uhd Jepsen, and S. R. Keiding, “THz reflection spectroscopy of liquid water,” Chem. Phys. Lett. 240, 330–333 (1995).
  9. J. T. Kindt and C. A. Schmuttenmaer, “Far-infrared dielectric properties of polar liquids probed by femtosecond terahertz pulse spectroscopy,” J. Phys. Chem. 100, 10373–10379 (1996).
  10. M. P. van Exter, C. Fattinger, and D. Grischkowsky, “Terahertz time-domain spectroscopy of water vapor,” Opt. Lett. 14, 1128–1130 (1989).
  11. D. M. Mittleman, R. H. Jacobsen, and M. C. Nuss, “T-ray imaging,” IEEE J. Sel. Top. Quantum Electron. 2, 679–692 (1996).
  12. B. B. Hu and M. C. Nuss, “Imaging with terahertz waves,” Opt. Lett. 20, 1716–1718 (1995).
  13. D. M. Mittleman, S. Hunsche, L. Boivin, and M. C. Nuss, “T-ray tomography,” Opt. Lett. 22, 904–906 (1997).
  14. Q. Wu, T. D. Hewitt, and X.-C. Zhang, “Two-dimensional electro-optic imaging of THz beams,” Appl. Phys. Lett. 69, 1026–1028 (1996).
  15. Z. Jiang and X.-C. Zhang, “Single-shot spatiotemporal terahertz field imaging,” Opt. Lett. 23, 1114–1116 (1998).
  16. J. O’Hara and D. Grischkowsky, “Quasi-optic terahertz imaging,” Opt. Lett. 26, 1918–1920 (2001).
  17. N. Katzenellenbogen and D. Grischkowsky, “Efficient generation of 380 fs pulses of THz radiation by ultrafast laser pulse excitation of a biased metal-semiconductor interface,” Appl. Phys. Lett. 58, 222–224 (1991).
  18. A. J. den Dekker and A. van den Bos, “Resolution: a survey,” J. Opt. Soc. Am. A 14, 547–557 (1997).
  19. A. B. Ruffin, J. Decker, L. Sanchez-Palencia, L. Le Hors, J. F. Whitaker, T. B. Norris, and J. V. Rudd, “Time reversal and object reconstruction with single-cycle pulses,” Opt. Lett. 26, 681–683 (2001).
  20. J. L. Johnson, T. D. Dorney, and D. M. Mittleman, “Interferometric imaging with terahertz pulses,” IEEE J. Sel. Top. Quantum Electron. 7, 592–599 (2001).
  21. S. Krishnamurthy, M. T. Reiten, S. A. Harmon, and R. A. Cheville, “Characterization of thin polymer films using terahertz time-domain interferometry,” Appl. Phys. Lett. 79, 875–877 (2001).
  22. J. O’Hara, “Experimental study of a quasi-optic synthetic phased-array terahertz imaging system,” Ph.D. dissertation (School of Electrical and Computer Engineering, Oklahoma State University, Stillwater, Okla., 2003).
  23. M. Ryle and A. Hewish, “The synthesis of large radio telescopes,” Mon. Not. R. Astron. Soc. 120, 220–230 (1960).
  24. P. J. Napier, A. R. Thompson, and R. D. Ekers, “The very large array: design and performance of a modern synthesis radio telescope,” Proc. IEEE 71, 1295–1322 (1983).
  25. P. J. Napier, D. S. Bagri, B. G. Clark, A. E. E. Rogers, J. D. Romney, A. R. Thompson, and R. C. Walker, “The very long baseline array,” Proc. IEEE 82, 658–672 (1994).
  26. A. Labeyrie, “Interference fringes obtained on Vega with two optical telescopes,” Astrophys. J. Lett. 196, L71–L75 (1975).
  27. A. R. Haijan and J. T. Armstrong, “A sharper view of the stars,” Sci. Am. 284, 56–63 (2001).
  28. A. Broquetas, J. Palau, L. Jofre, and A. Cardama, “Spherical wave near-field imaging and radar cross-section measurement,” IEEE Trans. Antennas Propag. 46, 730–735 (1998).
  29. D. Mensa, High Resolution Radar Imaging (Artech House, Dedham, Mass., 1981).
  30. T. D. Dorney, J. L. Johnson, J. Van Rudd, R. G. Baraniuk, W. W. Symes, and D. M. Mittleman, “Terahertz reflection imaging using Kirchhoff migration,” Opt. Lett. 26, 1513–1515 (2001).
  31. J. D. Kraus, Radio Astronomy (McGraw-Hill, New York, 1966).
  32. D. R. Wehner, High Resolution Radar (Artech House, Norwood, Mass., 1987).
  33. R. W. McGowan, R. A. Cheville, and D. R. Grischkowsky, “Experimental study of the surface waves on a dielectric cylinder via terahertz impulse radar ranging,” IEEE Trans. Microwave Theory Tech. 48, 417–422 (2000).
  34. J. J. Stamnes, Waves in Focal Regions (Adam Hilger, Bristol, England, 1986).
  35. J. W. Goodman, Introduction to Fourier Optics, 2nd ed. (McGraw-Hill, New York, 1996).
  36. E. Hecht, Optics, 4th ed. (Addison-Wesley, San Francisco, Calif., 2002).
  37. M. Born and E. Wolf, Principles of Optics, 7th ed. (Cambridge University, Cambridge, England, 1999).
  38. Y. Li and E. Wolf, “Three-dimensional intensity distribution near the focus in systems of different Fresnel numbers,” J. Opt. Soc. Am. A 1, 801–808 (1984).

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