Subwavelength three-dimensional frequency selective surface based on surface wave tunneling

Abstract

We propose a new type of three-dimensional frequency selective structure (3D-FSS) in form of subwavelength staggered metallic frames, and demonstrate a new design concept of confining and guiding surface wave propagation through the transmission tunnels for spacial filters. Both qualitative analysis by current loops and full-wave simulations show that the strong coupling along metallic frames can enhance the performance of frequency response, such as a sharper roll-off, clean out-of-band rejection, as well as angle and polarization insensitivity. Moreover, different unit cell shapes are introduced to confirm the universality of the design concept. Finally, a 3D-FSS with staggered rectangular frames was realized by experiment.

Frequency Selective Surfaces: A Review

“…Given the lumped element parameters along with structure geometry, the frequency responses of an FSS with an arbitrary number of cascading SIW cavities (1-8) can be obtained, and it is noticed from this reference that the transmission properties reach closer to the ideal passband transmission response. Additionally, the BW and insertion loss are not sensitive to the cavity count A novel design concept of guiding and confining the surface wave propagation through the transmission tunnels, by subwavelength metallic staggered rectangular frames, as shown in Figure 12a, has been utilized for spatial filtering as compared to earlier investigated planar surface structured waveguides [111]. A transmission curve with rectangular shape, sharp roll-off, and wider out-of-band rejection is obtained while five transmission poles within the passband (12.1 to 15.4 GHz) are observed.…”

“…(a) Surface waveguide made of metallic frames. (b) Coupling of current through Three-Dimensional FSS (3D FSS) structure at transmission poles[111].…”

Replication of periodic structure on 2D acrylic lens attained as a diffractive optical element in reflectance domain

“…This is basically because of time consuming, high cost and difficult in routine use. Besides, silicon, semiconductors, PMMA and PDMS as a structural material growing through variety of design choices by post processing technologies such as etching, coating, polishing, deposition and surface modification [4][5][6]. In addition, the modified and duplicate surface's structure of micro and nanometer level has an important belonging to a material property such as physical, electrical, mechanical and optical [7].…”

Roughness dependence of optical coefficient polarization on pixels’ diffractive elements by stretching technique

“…Provided its chemical material properties; its inert, non-toxic and surface is hydrophobic [1]. With other multipurpose properties such as viscoelastic with excellent optical and rheologic attributes [2], they are used as a structural material in microfluidic systems and biosensors often [3,4], narrowline feedback elements [5], tunable optical filters [6], polarization beam splitters [7], dispersion engineering [8], microwave frequency selective elements [9,10], and color filters [11][12][13]. By nature, the surface of PDMS is hydrophobic which presents a challenge in micro-channels.…”

“…Numerous treatments such as O 2 , C 2 F 2 , SF 6 , CF 4 , SiCl 4 , CCl 4 or mixture of the gases have been practical on PDMS surface to improve its hydrophobic properties. Besides, PDMS as a substrate or a structural material also growing according to the variety of design choices by post processing methods such as etching, coating, polishing, deposition and surface modification [1][2][3][4][5][6][7][8][9][10][11][12]. These efforts have merely been made specifically for PDMS enhancement and treatment, yet not any attempt is available on purely PDMS based properties as a substrate.…”