%0 Journal Article
%T Analysis of Frequency Leakage in Different Optical Paths of Nano-Metrology Systems Based on Frequency-Path Models
%J International Journal of Nanoscience and Nanotechnology
%I Iranian Nanotechnology Society
%Z 1735-7004
%A Olyaee, S.
%A Dashtban, Z.
%D 2014
%\ 06/01/2014
%V 10
%N 2
%P 79-96
%! Analysis of Frequency Leakage in Different Optical Paths of Nano-Metrology Systems Based on Frequency-Path Models
%K Frequency-path model
%K Interference terms
%K Heterodyne interferometer
%K Nano-metrology
%K Frequency
spectrum
%R
%X The drawing of frequency-path (F-P) models of optical beams is an approach for nonlinearity analysis in nano-metrology systems and sensors based on the laser interferometers. In this paper, the frequency-path models of four nano-metrology laser interferometry systems are designed, analyzed and simulated, including conventional and modified two- and three-longitudinal-mode laser interferometers. The frequency-path model can be used for nonlinearity error analysis resulting from imperfect alignment of optical head and non-ideal laser polarization states. The number of active F-P element in these systems is calculated by multiplying the number of frequency and paths. The number of active F-P elements for conventional and modified two-mode laser interferometer is 4, and this is 6 for conventional and modified three-mode laser interferometer. The output interference terms can be calculated from the active F-P elements which is 10 for conventional and modified two-mode interferometer and is 21 for conventional and modified three-mode one. The interference terms include optical power, ac interference, dc interference, and ac reference. These terms are also investigated in zero (fixed target), low (2mm/s), and high (20mm/s) target velocities using frequency spectrum of photocurrents.
%U http://www.ijnnonline.net/article_6113_2ad1a91b254b2e92de4fd174d5a326de.pdf