Post on 16-May-2018
IDENTIFYING AND CORRECTING INTRA-PIXEL VARIATIONS IN NEAR-INFRARED DETECTORS
The Spots-O-MaticMike Howe and Josh Larson
supervised by Prof. Greg Tarlé
July 29, 2010
SPOTS-O-MATICJoint Dark Energy MissionWide-field telescopeThe problem with undersampling
SPOTS-O-MATICWeak Lensing applicationsPrecision photometryNecessity of an understanding of intra-pixel variations (Spot-o-Matic)
SPOTS-O-MATICThe Spot-o-MaticMeasuring the intra-pixel response for one pixelLimitations with this approach for an entire detector
SPOTS-O-MATICFinding the PSF of our lens to ensure that variation in pixel response is possibleDetector characteristics:− HgCdTe imager
− 2048 x 2048 pixels
− 18 x 18 µm² pixel
In order to measure the intra-pixel variation we want a spot-size of, at most, 5µm in diameter
SPOTS-O-MATICKnife-Edge scan to determine the PSF of the lensMeasuring the integrated signal response of the projected spot across the knife-edge
SPOTS-O-MATICTaking a “derivative” to find a 1-dimensional Gaussian fitA fit sigma of 3µ would be small enough to scan the intra-pixel variations of the HgCdTe detectors
SPOTS-O-MATICFuture of the project
− Fabrication of all the necessary components
− Software development (more in a minute...)
SPOTS-O-MATIC
Four Separate ComponentsHardware ControlCalibrationData CollectionAnalysis
Software
SPOTS-O-MATIC
Hardware ControlImage AcquisitionStage Motion
Software
SPOTS-O-MATIC
CalibrationAligning and focusing the stageCurrently being tested with simulated data
Software
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Simulations will not usually be this extreme.
Software
SPOTS-O-MATIC
Future PlansCollection of actual dataAnalysisThis will all be done through simulations first
Software
SPOTS-O-MATICThank You!
Greg Tarlé
Michael Schubnell
Wolfgang Lorenzon
Curtis Weaverdyck
Tomasz Biesiadzinski
Ben Landes
Joel Xu
SPOTS-O-MATICQuestions?