SDO EVE CCD and Thin Foil Filter Characterization and Selection

Published

September 13, 2007

Author(s)

Matthew Triplett, David Croster, Thomas N. Woods, Francis Eparvier, Phillip Chamberlin, Gregory D. Berthiaume, David Weitz, Robert E. Vest

Abstract

The NASA Solar Dynamics Observatory (SDO), scheduled for launch in 2008, incorporates a suite of instruments including the EUV Variability Experiment (EVE). The EVE instrument package contains grating spectrographs used to measure the solar extreme ultraviolet (EUV) irradiance from 0.1 to 105 nm. The Multiple EUV Grating Spectrograph (MEGS) channels use concave reflection gratings to image solar spectra onto CCDs that are operated at -100 C. MEGS provides 0.1nm spectral resolution between 5-105nm every 10 seconds with an absolute accuracy of better than 25% over the SDO 5-year mission1. Characterizations and selection testing of the CCDs and the thin foil filters for SDO EVE have been performed with both in-band and visible illumination. CCD selection was based on results from testing in LASP facility CTE3 as well as results from MIT testing. All CCDs meet the requirements for electronics gain, flat field, QE, dark current, reverse clock, CTE, bad pixels and the -120 C survival test. The thin foil filters selection was based on tests performed at LASP facilities and NIST. All filters provide >106 attenuation of visible light with the proper transmission needed for order sorting capabilities and are free of critical pinholes.

Citation

SPIE Proceedings--The International Society for Optical Engineering

Pub Type

Journals

Keywords

CCD, EUV, EVE, MEGS, SDO, thin foil filter

Citation

Triplett, M. , Croster, D. , Woods, T. , Eparvier, F. , Chamberlin, P. , Berthiaume, G. , Weitz, D. and Vest, R. (2007), SDO EVE CCD and Thin Foil Filter Characterization and Selection, SPIE Proceedings--The International Society for Optical Engineering (Accessed October 8, 2025)