Methodology and results of straylight analysis for LSTM instrument

Alice Robert; Paul Jougla; Emilie Steck

doi:10.1117/12.3017489

17 June 2024 Methodology and results of straylight analysis for LSTM instrument

Alice Robert, Paul Jougla, Emilie Steck

Proceedings Volume 13019, Optical Design and Engineering IX; 130190L (2024) https://doi.org/10.1117/12.3017489
Event: SPIE Optical Systems Design, 2024, Strasbourg, France

Abstract

The Copernicus Land Surface Temperature Monitoring (LSTM) mission will perform spatial high temporal observations of land-surface in visible, near and thermal infrared bands. The LSTM mission requires very stringent straylight performances to meet the absolute radiometric accuracy, leading to straylight correction processing need. To get accurate correction, strong efforts are to be made to minimize the straylight level by optical design, over the mission wide spectral range. The LSTM instrument is currently under development at Airbus Defence and Space in Toulouse. The optical design is based on a dual freeform Three-Mirror Anastigmat telescope, including two-stages spectral filtering at intermediate and detector focal planes. The design optimization is mainly driven by straylight rejection, either in a geometrical or in a spectral way. A complete straylight model of the instrument is developed, including optics and mechanics, with their respective coatings and scattering models, using non-sequential raytracing software. We perform ghosts and scatter simulations in the frame of instrument PDR, taking into account multispectral effects. The straylight simulations include very detailed features, such as introduction of coating listels or computation of ghost spectrum. The methodology used for baffle optimization is described, especially slit masks implemented on spectral filter subassemblies, at each focal plane. A parametric study is performed, to get an optimized parameters set for each mask, ensuring meeting straylight performances, and taking into account footprint tolerancing, manufacturing and alignment.

Conference Presentation

Citation Download Citation

Alice Robert, Paul Jougla, and Emilie Steck "Methodology and results of straylight analysis for LSTM instrument", Proc. SPIE 13019, Optical Design and Engineering IX, 130190L (17 June 2024); https://doi.org/10.1117/12.3017489

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available