OSA's Digital Library

Journal of the Optical Society of America A

Journal of the Optical Society of America A

| OPTICS, IMAGE SCIENCE, AND VISION

  • Vol. 1, Iss. 9 — Sep. 1, 1984
  • pp: 965–973

Focusing of electromagnetic waves through a dielectric interface

Hao Ling and Shung-Wu Lee  »View Author Affiliations


JOSA A, Vol. 1, Issue 9, pp. 965-973 (1984)
http://dx.doi.org/10.1364/JOSAA.1.000965


View Full Text Article

Enhanced HTML    Acrobat PDF (1010 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

Given a time-harmonic electric-current distribution over a finite planar aperture situated in front of a dielectric half-space, the transmitted field in the dielectric half-space is calculated by the plane-wave-spectrum technique. We concentrate on the current distribution that focuses the electromagnetic energy into a small spot in the dielectric medium, such as in hyperthermia applications. Numerical results are given to illustrate the variation of spot size and of focal-point electric-field intensity as functions of polarization, scanning, and the permittivity of the half-space. We find that (1) the maximum electric-field intensity is not at the focal point but rather at a point closer to the aperture; for a small aperture, this focal shift may be more than one wavelength; (2) when the dielectric half-space is introduced, the 3-dB spot size changes according to the ratio of the wavelength in the half-space to that in the original aperture medium; and (3) the electric-field intensity at the focal point is greatest when the permittivity of the half-space is less than that of the aperture medium, not when the two media are electrically matched.

© 1984 Optical Society of America

History
Original Manuscript: October 17, 1983
Manuscript Accepted: May 14, 1984
Published: September 1, 1984

Citation
Hao Ling and Shung-Wu Lee, "Focusing of electromagnetic waves through a dielectric interface," J. Opt. Soc. Am. A 1, 965-973 (1984)
http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-1-9-965


Sort:  Author  |  Year  |  Journal  |  Reset  

References

  1. M. Born, E. Wolf, Principles of Optics, 2nd ed. (Pergamon, New York, 1964), Sec. 8.8.
  2. H. C. Minnett, B. MacA. Thomas, “Fields in the image space of symmetrical focusing reflectors,” Proc. IEE 115, 1419–1430 (1968).
  3. M. Landry, Y. Chassé, “Measurements of electromagnetic field intensity in focal region of wide-angle paraboloid reflector,” IEEE Trans. Antennas Propag. AP-19, 539–543 (1971). [CrossRef]
  4. C. C. Hung, R. Mittra, “Secondary pattern and focal region distribution of reflector antennas under wide-angle scanning,” IEEE Trans. Antennas Propag. AP-31, 756–763 (1983). [CrossRef]
  5. J. J. Stamnes, “Focusing of two-dimensional waves,” J. Opt. Soc. Am. 71, 15–31 (1981). [CrossRef]
  6. J. J. Stamnes, “New methods for computing fields in focal regions,” Soc. Photo-Opt. Instrum. Eng. 358, 184–191 (1982).
  7. J. J. Stamnes, “The Luneburg apodization problem in the non-paraxial domain,” Opt. Commun. 38, 325–329 (1981). [CrossRef]
  8. J. J. Stamnes, “Focusing of a perfect wave and the Airy pattern formula,” Opt. Commun. 37, 311–314 (1981). [CrossRef]
  9. E. Wolf, Y. Li, “Conditions for the validity of the Debye integral representation of focused fields,” Opt. Commun. 39, 205–210 (1981). [CrossRef]
  10. J. J. Stamnes, B. Spjelkavik, “Focusing at small angular apertures in the Debye and Kirchhoff approximations,” Opt. Commun. 40, 81–85 (1981). [CrossRef]
  11. Y. Li, E. Wolf, “Focal shifts in diffracted converging spherical waves,” Opt. Commun. 39, 211–215 (1981). [CrossRef]
  12. Y. Li, “Dependence of the focal shift on Fresnel number and f number,” J. Opt. Soc. Am. 72, 770–774 (1982). [CrossRef]
  13. M. P. Givens, “Focal shifts in diffracted converging spherical waves,” Opt. Commun. 41, 145–148 (1982). [CrossRef]
  14. Y. Li, “Encircled energy of diffracted converging spherical waves,” J. Opt. Soc. Am. 73, 1101–1104 (1983). [CrossRef]
  15. H. Ling, S. W. Lee, W. Gee, “Frequency optimization of focused microwave hyperthermia applicators,” Proc. IEEE 72, 224–225 (1984). [CrossRef]
  16. J. Gasper, G. C. Sherman, J. J. Stamnes, “Reflection and refraction of an arbitrary electromagnetic wave at a plane interface,” J. Opt. Soc. Am. 66, 955–961 (1976). [CrossRef]
  17. R. F. Harrington, Time-Harmonic Electromagnetic Fields (McGraw-Hill, New York, 1961), p. 130.
  18. M. Born, E. Wolf, Principles of Optics, 2nd ed. (Pergamon, New York, 1964), App. III.
  19. S. W. Lee, M. S. Sheshadri, V. Jamnejad, R. Mittra, “Refraction at a curved dielectric interface: geometrical optics solution,” IEEE Trans. Microwave Theory Tech. MTT-30, 12–19 (1982).
  20. L. B. Felsen, N. Marcuvitz, Radiation and Scattering of Waves (Prentice-Hall, Englewood Cliffs, N.J., 1973), Sec. 5.5.
  21. G. C. Sherman, J. J. Stamnes, E. Lalor, “Asymptotic approximations to angular-spectrum representations,” J. Math. Phys. 17, 760–776 (1976). [CrossRef]
  22. W. Gee, S. W. Lee, N. Bong, C. Cain, R. Mittra, R. Magin, “Focused array hyperthermia applicator: theory and experiment,” IEEE Trans. Biomed. Eng. BME-31, 38–46 (1984). [CrossRef]
  23. A. Boivin, E. Wolf, “Electromagnetic field in the neighborhood of the focus of a coherent beam,” Phys. Rev. B 138, 1561–1565 (1965). [CrossRef]
  24. L. J. Ricardi, “Near-field characteristics of a linear array,” in Electromagnetic Theory and Antennas, E. C. Jordan, ed. (Pergamon, New York, 1962).
  25. J. W. Sherman, “Properties of focused apertures in the Fresnel region,” IRE Trans. Antennas Propag. AP-10, 399–408 (1962). [CrossRef]
  26. M. P. Bachynski, G. Bekefi, “Study of optical diffraction images at microwave frequencies,” J. Opt. Soc. Am. 47, 428–438 (1957). [CrossRef]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.


« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited