Diffraction Of An Electromagnetic Wave By A New Type Of Crossed Grating

Roger Deleuil; Elvino Toro

doi:10.1117/12.944837

12 December 1984 Diffraction Of An Electromagnetic Wave By A New Type Of Crossed Grating

Roger Deleuil, Elvino Toro

Proceedings Volume 0503, Application, Theory, and Fabrication of Periodic Structures, DiffractionGratings, and Moire Phenomena II; (1984) https://doi.org/10.1117/12.944837
Event: 28th Annual Technical Symposium, 1984, San Diego, United States

Abstract

A theoretical and experimental study of the diffraction of an electromagnetic wave by a plane metallic crossed grating of hemispherical cavities is presented here. The cavities with radius R are periodically hollowed along two perpendicular directions x'x and z'z; the periods are A and B respectively. This crossed grating is illuminated at arbitrary incidence by a linearly polarized harmonic plane wave with wavelength λ. To solve this problem theoretically we use a modal method. Within the cavities the field is expanded in terms of spherical wave functions and above the grating surface the total field is written as the sum of the incident field and of the diffracted one (which is expressed as a Rayleigh expansion). Two types of boundary conditions are then considered. Firstly, on the metallic surface the tangential components of the electric field cancel. Secondly, on the plane circular surface limiting the hemispherical cavity from the free-space the fields on both sides are matched. Thus, we obtain a set of algebraic equations which are then resolved by means of a least squares method. The numerical results concern the particular case of normal incidence which leads to simpler calculus. We show that the efficiency in the (0,0) order (noted ε(0,0)) is widely dependent on the ratio R/λ and with appropriate values of R/λ and A/λ very low values of ε(0,0) can be obtained. An experimental study is carried out in the microwave range (λ ≈ 8.6 mm) with two metallic crossed gratings having the same periods A E B = 13 mm and radii R1 = 4 mm and R2 = 6 mm. The experiments concern the variations of ε(0,0) versus the angle of incidence and the two cases of polarization (T.E. and T.M.) are investigated.

Citation Download Citation

Roger Deleuil and Elvino Toro "Diffraction Of An Electromagnetic Wave By A New Type Of Crossed Grating", Proc. SPIE 0503, Application, Theory, and Fabrication of Periodic Structures, DiffractionGratings, and Moire Phenomena II, (12 December 1984); https://doi.org/10.1117/12.944837

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
7 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Diffraction gratings

Diffraction

Electromagnetic radiation

Electromagnetism

Microwave radiation

Polarization

Calculus

Show All Keywords

Keywords/Phrases

Search In:

Publication Years