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Title: Smartphone Screens as Astrometric Calibrators
Geometric optical distortion is a significant contributor to the astrometric error budget in large telescopes using adaptive optics. To increase astrometric precision, optical distortion calibration is necessary. We investigate using smartphone Organic Light-Emitting Diode (OLED) screens as astrometric calibrators. Smartphones are low-cost, have stable illumination, and can be quickly reconfigured to probe different spatial frequencies of an optical system’s geometric distortion. In this work, we characterize the astrometric accuracy of a Samsung S20 smartphone, with a view towards providing large format, flexible astrometric calibrators for the next generation of astronomical instruments. We find the placement error of the pixels to be 189[Formula: see text]nm ± 15[Formula: see text]nm Root Mean Square (RMS). At this level of error, milliarcsecond astrometric accuracy can be obtained on modern astronomical instruments.  more » « less
Award ID(s):
2108185
NSF-PAR ID:
10447771
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Astronomical Instrumentation
ISSN:
2251-1717
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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