Abstract

Wood’s anomalies are investigated by using a microwave spectrometer operating at a wavelength of 3.8 mm. For S-polarization, high surface conductivity, periodicities of 2λ and 3λ, and groove depths from λ/8 to (5λ)/4, rectangular profile gratings are shown to exhibit anomalies which can be explained by simple interference between the orders due to the incident beam and the orders due to the passing-off order if it is considered as a second beam incident at ±90°. Artificial passing-off orders are formed, and these permit one to change the natural anomalies from bright to dark and vice versa. Interference of the orders owing to the incident and imposed beams at anomalous angles is demonstrated by measuring the power in each of the overlapping orders separately and comparing the sum of their amplitudes with the value measured at the anomalous angle. For all cases tested the results are satisfactory for either bright or dark anomalies. By adjusting the angle of a second incident beam to calculated values, artificial anomalies, i.e., anomalies at angles of incidence where they do not normally occur, are created. These anomalies cannot be distinguished from their natural counterparts.

© 1966 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. R. W. Wood, Proc. Phys. Soc. (London) 18, 396 (1902).
  2. Rayleigh, Proc. Roy. Soc. (London) A79, 399 (1907).
  3. C. H. Palmer, J. Opt. Soc. Am. 42, 269 (1952).
    [Crossref]
  4. W. Voigt, Nachr. Math. Phys. K1, 40 (1911).
  5. U. Fano, Ann. Phys. 32, 393 (1938).
    [Crossref]
  6. K. Artmann, Z. Physik 119, 529 (1942).
    [Crossref]
  7. V. Twersky, J. Opt. Soc. Am. 52, 145 (1962).
    [Crossref]
  8. A. Hessel, A. A. Oliner, Appl. Opt. 4, 1275 (1965).
    [Crossref]
  9. L. R. Ingersoll, J. Astrophys. 51, 291 (1935).
  10. J. Strong, Phys. Rev. 49, 291 (1935).
    [Crossref]
  11. J. E. Stewart, W. S. Galloway, Appl. Opt. 1, 421 (1962).
    [Crossref]
  12. C. H. Palmer, in Symposium on Quasi-Optics (Polytechnic Press, Brooklyn, N.Y., 1964).
  13. C. H. Palmer, F. C. Evering, J. Opt. Soc. Am. 54, 844 (1964).
    [Crossref]
  14. C. H. Palmer, F. C. Evering, F. Nelson, Appl. Opt. 4, 1271 (1965).
    [Crossref]

1965 (2)

1964 (1)

1962 (2)

1952 (1)

1942 (1)

K. Artmann, Z. Physik 119, 529 (1942).
[Crossref]

1938 (1)

U. Fano, Ann. Phys. 32, 393 (1938).
[Crossref]

1935 (2)

L. R. Ingersoll, J. Astrophys. 51, 291 (1935).

J. Strong, Phys. Rev. 49, 291 (1935).
[Crossref]

1911 (1)

W. Voigt, Nachr. Math. Phys. K1, 40 (1911).

1907 (1)

Rayleigh, Proc. Roy. Soc. (London) A79, 399 (1907).

1902 (1)

R. W. Wood, Proc. Phys. Soc. (London) 18, 396 (1902).

Artmann, K.

K. Artmann, Z. Physik 119, 529 (1942).
[Crossref]

Evering, F. C.

Fano, U.

U. Fano, Ann. Phys. 32, 393 (1938).
[Crossref]

Galloway, W. S.

Hessel, A.

Ingersoll, L. R.

L. R. Ingersoll, J. Astrophys. 51, 291 (1935).

Nelson, F.

Oliner, A. A.

Palmer, C. H.

Rayleigh,

Rayleigh, Proc. Roy. Soc. (London) A79, 399 (1907).

Stewart, J. E.

Strong, J.

J. Strong, Phys. Rev. 49, 291 (1935).
[Crossref]

Twersky, V.

Voigt, W.

W. Voigt, Nachr. Math. Phys. K1, 40 (1911).

Wood, R. W.

R. W. Wood, Proc. Phys. Soc. (London) 18, 396 (1902).

Ann. Phys. (1)

U. Fano, Ann. Phys. 32, 393 (1938).
[Crossref]

Appl. Opt. (3)

J. Astrophys. (1)

L. R. Ingersoll, J. Astrophys. 51, 291 (1935).

J. Opt. Soc. Am. (3)

Nachr. Math. Phys. (1)

W. Voigt, Nachr. Math. Phys. K1, 40 (1911).

Phys. Rev. (1)

J. Strong, Phys. Rev. 49, 291 (1935).
[Crossref]

Proc. Phys. Soc. (London) (1)

R. W. Wood, Proc. Phys. Soc. (London) 18, 396 (1902).

Proc. Roy. Soc. (London) (1)

Rayleigh, Proc. Roy. Soc. (London) A79, 399 (1907).

Z. Physik (1)

K. Artmann, Z. Physik 119, 529 (1942).
[Crossref]

Other (1)

C. H. Palmer, in Symposium on Quasi-Optics (Polytechnic Press, Brooklyn, N.Y., 1964).

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)

Fig. 1
Fig. 1

Diffraction orders of the incident beam and the passing-off orders considered as separate beams. Grating equation: nλ = d(sini + sinr), where d = 2λ. Angles clockwise from grating normal are negative. Angles counterclockwise from grating normal are positive.

Fig. 2
Fig. 2

Spectrometer.

Fig. 3
Fig. 3

Details of reflector mount.

Fig. 4
Fig. 4

Angle designations for Eq. (2). i1 = angle of incidence of main beam (drawn negative). i2 = angle of incidence of beam from metal reflector (drawn negative). ϕ = angle of reflector with grating surface.

Fig. 5
Fig. 5

Altering a natural anomaly. The anomaly is changed from a dark 4 dB to a dark 9 dB and to a bright 5 dB. For clarity no data points are shown on succeeding drawings. Grating T-5; sixteen lines. S-polarization. n = −1. — —reflector adjusted for a maximum at <i = −30.5°. - - - reflector covered with absorber (20 dB). ——reflector adjusted for a minimum at <i = −30.5°.

Fig. 6
Fig. 6

Arrangement for measuring the power in the orders due to the beam from the reflector.

Fig. 7
Fig. 7

Creating an anomaly. Grating T-5. S-polarization. n = +1. — — reflector adjusted for a maximum at <i = −20°. - - - reflector covered. —— reflector adjusted for a minimum at <i = −20°.

Tables (2)

Tables Icon

Table I Grating Specifications, λ = 3.8 mm

Tables Icon

Table II Results for Altered and Created Anomalies

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

n λ = d ( sin i ± 1 ) ,
n 1 - n 2 = d λ [ sin i 1 - sin ( 2 ϕ - 180 ° - i 1 ) i 2 ] .

Metrics