Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published July 12, 2018 | Published + Submitted
Book Section - Chapter Open

Intra-pixel response characterization of a HgCdTe near infrared detector with a pronounced crosshatch pattern


The "crosshatch" pattern is a recurring "feature" of HgCdTe arrays, specifically the Teledyne HAWAII family of near infrared detectors. It is a fixed pattern of high frequency QE variations along 3 directions generally thought to be related to the crystal structure of HgCdTe. The pattern is evident in detectors used in WFC3/IR, WISE, JWST, and in candidate detectors for Euclid and WFIRST. Using undersampled point sources projected onto a HAWAII-2RG detector, we show that the pattern induces photometric variations that are not removed by a flat-field calibration, thus demonstrating that the QE variations occur on scales smaller than the 18 micron pixels. Our testbed is the Precision Projector Laboratory's astronomical scene generator, which can rapidly characterize the full detector by scanning thousands of undersampled spots. If not properly calibrated, detectors showing strong crosshatch may induce correlated errors in photometry, astrometry, spectroscopy, and shape measurements.

Additional Information

© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). Thanks to Warren Holmes and the Euclid detector working group for lending the H2RG detector used in this research. Thanks to Dave Hale and Alex Delacroix for helping to get the detector up and running. Thanks also to Mike Seiffert, Stefanie Wachter, and Chris Hirata for valuable insights and critiques of this research. This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Facility space and support for PPL is provided by Caltech Optical Observatories.

Attached Files

Published - 1070936.pdf

Submitted - 1806.11185.pdf


Files (7.8 MB)
Name Size Download all
5.6 MB Preview Download
2.2 MB Preview Download

Additional details

August 19, 2023
January 14, 2024