Share Email Print
cover

Proceedings Paper

Liquid crystals Lyot filter for solar coronagraphy
Author(s): S. Fineschi; G. Capobianco; G. Massone; T. Baur; A. Bemporad; L. Abbo; L. Zangrilli; V. Dadeppo
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The "Association de Satellites Pour l'Imagerie et l'Interférométrie de la Couronne Solaire", ASPIICS, is a solar coronagraph to be flown on the PROBA 3 Technology mission of the European Space Agency. ASPIICS heralds the next generation of coronagraphs for solar research, exploiting formation flying to gain access to the inner corona under eclipse-like conditions in space. The science goal is high spatial resolution imaging and two-dimensional spectrophotometry of the Fe XIV, 530.3 nm, emission line. This work describes a liquid crystal Lyot tunable-filter and polarimeter (LCTP) that can implement this goal. The LCTP is a bandpass filter with a full width at half maximum of 0.15 nm at a wavelength of 530.3 nm. The center wavelength of the bandpass is tunable in 0.01 nm steps from 528.64 nm to 533.38 nm. It is a four stage Lyot filter with all four stages wide-fielded. The free spectral range between neighboring transmission bands of the filter is 2.7 nm. The wavelength tuning is non-mechanical using nematic liquid crystal variable retarders (LCVR's). A separate LCVR of the Senarmont design, in tandem with the filter, is used for the polarimetric measurements. A prototype of the LCTP has been built and its measured performances are presented here.

Paper Details

Date Published: 12 October 2011
PDF: 10 pages
Proc. SPIE 8148, Solar Physics and Space Weather Instrumentation IV, 814808 (12 October 2011); doi: 10.1117/12.897793
Show Author Affiliations
S. Fineschi, INAF - Osservatorio Astronomico di Torino (Italy)
G. Capobianco, INAF - Osservatorio Astronomico di Torino (Italy)
G. Massone, INAF - Osservatorio Astronomico di Torino (Italy)
T. Baur, Meadowlark Optics, Inc. (United States)
A. Bemporad, INAF - Osservatorio Astronomico di Torino (Italy)
L. Abbo, INAF - Osservatorio Astronomico di Torino (Italy)
L. Zangrilli, INAF - Osservatorio Astronomico di Torino (Italy)
V. Dadeppo, CNR IFN LUXOR Lab. (Italy)


Published in SPIE Proceedings Vol. 8148:
Solar Physics and Space Weather Instrumentation IV
Silvano Fineschi; Judy Fennelly, Editor(s)

© SPIE. Terms of Use
Back to Top