scholarly journals Common-path holographic interferometer for flatness testing

1994 ◽  
Author(s):  
Pierre M. Jacquot ◽  
Xavier Colonna de Lega ◽  
Pierre M. Boone
Keyword(s):  
Common Path ◽  
Holographic Interferometer

Non-common Path Aberrations measurement using the NWIWM method

2017 ◽  
Author(s):  
Luis Fernando Rodríguez Ramos ◽  
Javier López Campos ◽  
Oscar Tubío Araújo ◽  
Carlos Colodro Conde ◽  
Miguel Núñez Cagigal ◽  
...  
Keyword(s):  
Common Path

scholarly journals Nano-imprinted subwavelength gratings as polarizing beamsplitters

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Julian Wüster ◽  
Yannick Bourgin ◽  
Patrick Feßer ◽  
Arne Behrens ◽  
Stefan Sinzinger
Keyword(s):  
Nanoimprint Lithography ◽  
Optical Measurement ◽  
Design Method ◽  
Optical Systems ◽  
Surface Metrology ◽  
Measurement Systems ◽  
Common Path ◽  
Dielectric Coatings ◽  
Subwavelength Gratings ◽  
Wide Range

AbstractPolarizing beamsplitters have numerous applications in optical systems, such as systems for freeform surface metrology. They are classically manufactured from birefringent materials or with stacks of dielectric coatings. We present a binary subwavelength-structured form-birefringent diffraction grating, which acts as a polarizing beamsplitter for a wide range of incidence angles −30∘…+30∘. We refine the general design method for such hybrid gratings. We furthermore demonstrate the manufacturing steps with Soft-UV-Nanoimprint-Lithography, as well as the experimental verification, that the structure reliably acts as a polarizing beamsplitter. The experimental results show a contrast in efficiency for TE- and TM-polarization of up to 1:18 in the first order, and 34:1 in the zeroth order. The grating potentially enables us to realize integrated compact optical measurement systems, such as common-path interferometers.

Simulation and analysis of the coherent-dispersion spectrometer for exoplanet detection

2021 ◽  
Vol 503 (2) ◽  
pp. 3032-3043
Author(s):  
Yinhua Wu ◽  
Shasha Chen ◽  
Pengchong Wang ◽  
Shun Zhou ◽  
Yutao Feng ◽  
...  
Keyword(s):  
Data Processing ◽  
Michelson Interferometer ◽  
Energy Utilization ◽  
Design Stage ◽  
Inversion Method ◽  
Fringe Visibility ◽  
Common Path ◽  
Data Processing Method ◽  
Detection Instrument ◽  
Performance Research

ABSTRACT The coherent-dispersion spectrometer (CODES) is a new exoplanet detection instrument using the radial velocity (RV) method. This attempts mainly to improve environmental sensitivity and energy utilization by using an asymmetric, common-path Sagnac interferometer instead of a traditional Michelson interferometer. In order to verify its feasibility and to choose the appropriate key parameters to obtain the optimal performance, research on data processing for the design stage of the CODES is performed by systematic simulation and analysis. First, the instrument modelling is carried out for further data analysis according to the principle of the CODES, and the reliability of the model is verified by experiments. Second, the influence of key parameters on fringe visibility is analysed systematically, which provides a certain reference for the choice of the key parameters. Third, the RV inversion method for the CODES is proposed and optimized according to the related analysis results so as to promote RV inversion precision. Finally, the recommended values for the key parameters of the CODES are given. The experimental results show that the data processing error of RV inversion is less than 0.6 m s–1 within the recommended range of key parameters. This indicates that the scheme of the CODES is reasonable and feasible, and that the proposed data processing method is effective and well matched with the instrument design.

scholarly journals Minority stress, resilience, and health in Italian and Taiwanese LGB+ people: A cross-cultural comparison

2021 ◽  
Author(s):  
Roberto Baiocco ◽  
Cristiano Scandurra ◽  
Fausta Rosati ◽  
Jessica Pistella ◽  
Salvatore Ioverno ◽  
...  
Keyword(s):  
Minority Stress ◽  
Online Survey ◽  
Health Problems ◽  
Sexual Stigma ◽  
Common Path ◽  
Mediating Role ◽  
Cross Cultural Comparison ◽  
Moderated Mediation Model ◽  
The Relationship

AbstractThe present study, using a moderated mediational model, explored levels of distal/proximal stressors, rumination, resilience, and health in a group of Italian and Taiwanese LGB+ people. The study also examined the role of internalized sexual stigma (ISS) and rumination as mediators between discrimination and health, and resilience as a moderator of the relationship between discrimination and ISS, rumination, and health, respectively. An online survey was administered to 508 LGB+ participants (270 Italian and 238 Taiwanese) whose age ranged from 18 to 70 years (M = 37.93, SD = 13.53). The moderated mediation model was tested through a series of path analyses stratified by group nationality. Italian participants reported higher discrimination and resilience, but lower ISS, rumination, and health problems compared to their Taiwanese counterparts. The only common path between groups was the direct effect of discrimination on health problems. The mediating role of ISS and rumination in the relationship between discrimination and health, as well as the moderating role of resilience, were partly significant only for the Italian group. Conclusions: The findings suggest that mediators and moderators used to evaluate the effects of minority stress on health may differ between groups; further culturally sensitive research in the field of LGB+ health is needed.

Research of Zero Calibration in Conoscopic Holography Measurement Based on Image

2013 ◽  
Vol 303-306 ◽  
pp. 386-389
Author(s):  
Shu Yan Ren ◽  
Yong Gang Yang ◽  
Hai Long Duan
Keyword(s):  
Extreme Points ◽  
B Splines ◽  
Contact Measurement ◽  
Measurement Result ◽  
Common Path ◽  
Repeatability Error ◽  
Zero Position ◽  
Conoscopic Holography ◽  
Patch Image ◽  
Method Of Adjustment

Non-contact measurement based on conoscopic holography is a kind of interferometry with common path, so it is not influenced much by other factors such as vibration. But the measurement result is affected by the uniformity of the crystal, which is analyzed in this paper, and corresponding method of adjustment based on image is discussed. And B-splines function is used to calculate zero position in measurement image, which is fitted over the patch image in the neighborhood of gray extreme points of the stripes, which is important to reduce the repeatability error, optimize design, and improve the accuracy of system.

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