Share Email Print

Proceedings Paper

Development of the Savart-plate lateral-shearing interferometric nuller for exoplanet (SPLINE)
Author(s): Naoshi Murakami; Manabu Kida; Naoshi Baba; Taro Matsuo; Takayuki Kotani; Hajime Kawahara; Yuka Fujii; Motohide Tamura
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The Savart-Plate Lateral-shearing Interferometric Nuller for Exoplanet (SPLINE) is a stable and fully achromatic nulling interferometer proposed for direct detection of extrasolar planets with segmented-mirror telescopes like the Thirty Meter Telescope (TMT). The SPLINE uses a Savart plate, a kind of polarizing beam splitter, to split a light beam into two orthogonally polarized ones with a lateral shift. The Savart plate placed between crossed polarizers causes fully achromatic destructive interference for an on-axis star light. On the other hand, planetary light from an off-axis direction does not destructively interfere due to the lateral shift. The SPLINE provides a stable interferometric output because of its simple common-path optical design without an optical-path difference control system. We carried out laboratory demonstrations of the SPLINE to evaluate its stability, achromaticity, and achievable contrast. As a result, a high contrast of >104 (peak-to-peak contrast) is achieved using a broadband light source as a star model. In addition, we also propose to apply a differential imaging technique to the SPLINE for improving achievable contrast. We report our recent activities and show the results of the laboratory demonstrations.

Paper Details

Date Published: 24 September 2012
PDF: 8 pages
Proc. SPIE 8446, Ground-based and Airborne Instrumentation for Astronomy IV, 84468H (24 September 2012); doi: 10.1117/12.925605
Show Author Affiliations
Naoshi Murakami, Hokkaido Univ. (Japan)
Manabu Kida, Hokkaido Univ. (Japan)
Naoshi Baba, Hokkaido Univ. (Japan)
Taro Matsuo, Kyoto Univ. (Japan)
National Astronomical Observatory of Japan (Japan)
Takayuki Kotani, National Astronomical Observatory of Japan (Japan)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (Japan)
Hajime Kawahara, Tokyo Metropolitan Univ. (Japan)
Yuka Fujii, The Univ. of Tokyo (Japan)
Motohide Tamura, National Astronomical Observatory of Japan (Japan)

Published in SPIE Proceedings Vol. 8446:
Ground-based and Airborne Instrumentation for Astronomy IV
Ian S. McLean; Suzanne K. Ramsay; Hideki Takami, Editor(s)

© SPIE. Terms of Use
Back to Top