Design and fabrication of sub-wavelength metal wire-grid and its application to experimental study of polarimetric imaging

The present paper utilizes the Green function method to analyze the scattering properties of the metal wire grating in the THz band, and further to study the influence of the diffraction on the transfer characteristic of the metal wire grating. Results prove that the transmission amplitude of the incident electromagnetic wave is increasing monotonously with the enlargement of the value of a/, and it arrives at the maximum in the zero-order diffraction limit. Due to the strengthened effect of diffraction, transmission curves of the incident electromagnetic wave show oscillation in the critical frequency transition region. Due to the diffraction effect, the transmission amplitude of the incident electromagnetic wave demonstrates an overall decline in the diffraction zone, and it is decreasing monotonously with the enlargement in the value of a/. Compared with microwave transmission line method, this method can aliminate the restriction that the wavelength of the incident electromagnetic wave must be greater than the wire grating constant, and the thickness of wire grating must be far less than the metal line width. This method could be used to analyze the distribution of the electromagnetic properties of the system accurately; and it will be a generally suitable one.

show abstract

Spatial phase-shifting polarization point-piffraction interferometer for wavefront measurement

Zheng¹,

Li²,

Chen³

et al. 2016

Acta Phys. Sin.

View full text Add to dashboard Cite

Wavefront measurement is widely used in the field of optical manufacturing, military, astronomy, medical treatment, etc., and it reflects the performance of the optical system through evaluating aberrations. Relevant studies have been carried out by many researchers. Among them, point-diffraction interferometer and spatial phase-shifting interferometer are two significant instruments for the wavefront measurement. Point-diffraction interferometer is a simple self-referencing configuration with high precision, and spatial phase-shifting interferometer can be used in the vibration environment or for measuring the dynamic object. Owing to these advantages, they have been widely used in the field of wavefront measurement. In this paper, to realize the combination of these two techniques, we propose a new method of fabricating a polarization point-diffraction plate. Through laser drilling technology, we fabricate a pinhole at a micron level on a wire grid polarizer with a period and depth of 140 nm and 100 nm respectively, and fabricate a polarization point-diffraction plate. We analyze the principle of laser drilling, the orthogonally polarized reference beam and test beam generation mechanism of the polarization point-diffraction plate. The principle of spatial phase-shifting interferometer is deduced by adopting Stokes vector and mueller matrix. Combining with the spatial phase-shifting system with beam splitter, a spatial phase-shifting polarization point-diffraction interferometer is built. In the experimental apparatus, the diameter of the pinhole on the polarization point-diffraction plate is 10.2 m, the beam splitter is a chessboard phase grating whose period, duty cycle, and etched depth are 34 m, 0.5, and 577 nm respectively, and the phase-shifting component is a 22 wave-plate array which is glued together with a 1/4 wave-plate, a 1/2 wave-plate, a 3/4 wave-plate and a full wave-plate; the four fast-axes of the wave-plates are all along the horizontal direction. The spatial phase-shifting polarization point-diffraction interferometer is used to measure the transmitted wavefront through a collimating lens with a focal length of 550 mm and F#10 which are used on a collimator. The measured peak-to-valley value, root-mean-square value and Zernike fitting coefficients are in good agreement with those obtained by SID4 wavefront sensor made by Phasics corporation in France, which verifies the reliability of the measuring results obtained by spatial phase-shifting polarization point-diffraction interferometer. The spatial phase-shifting polarization point-diffraction interferometer introduces spatial phase-shifting technology into traditional point-diffraction interferometer, thereby achieving real-time wavefront measurement with high resolution and precision, and also improving the immunity to vibration, air turbulence, etc.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Design and fabrication of sub-wavelength metal wire-grid and its application to experimental study of polarimetric imaging

Cited by 3 publications

References 7 publications

Broadband polarizing beam splitter based on two-layer metal grating with a high refractive index dielectric layer

Broadband polarizing beam splitter based on two-layer metal grating with a high refractive index dielectric layer

Study on scattering properties of the metal wire gating in a THz band based on Green function method

Spatial phase-shifting polarization point-piffraction interferometer for wavefront measurement

Contact Info

Product

Resources

About