Charge Injection Devices (CIDs) have demonstrated direct contrast ratios in excess of 1:20 million from suboptimal ground-based astronomical observations. CIDs are therefore interesting prospects for obtaining direct images from a host of high contrast ratio celestial scenes. However, while CIDs are capable of much deeper contrast ratios, potentially exceeding 1:1 billion, they do not address the Inner Working Angle (IWA) problem. If the Point-Spread Function (PSF) of a bright target is not well understood and accounted for, then the IWA will be large and nearby faint objects, like exoplanets, will be challenging to observe regardless of the detector used. As Earth's atmosphere is a major contributor to the variability of a PSF, high contrast ratio imaging with small IWAs will be best achieved in space. Therefore, if CIDs are to be used on future space-telescopes, they must be flight qualified in the space environment and shown to be at the appropriate Technology Readiness Level (TRL). Here we report the results of an 8 months CID technology demonstration mission that used the Nano-Racks External Platform mounted to the Kibo Exposed Facility on-board the International Space Station. Over the course of the 236 days mission we find no significant on-orbit changes of CID performance in terms of dark current, linearity, read noise, and photon transfer efficiency. As a result, CIDs are now space-qualified to TRL-8 and can be considered for future space telescopes.

The intrinsic nature of many astronomical objects, such as binary systems, exoplanets, circumstellar disks, and quasar host galaxies, introduces challenging requirements on observational instrumentation and techniques. In each case, we encounter situations where the light from bright sources completely outshines the surrounding faint targets. As a result, we are yet to fully understand the processes governing star and galaxy formation and evolution, and there are ongoing attempts to search for habitable worlds around other stars. To explore all features of such astronomical objects, we must perform observations at the maximum possible contrast ratios. Here, we demonstrate the extreme contrast ratio imaging capabilities of the latest generation of commercially available charge injection devices, the SpectraCAM XDR, using Sirius field observations from a world-class observing site. Based on wavelet-based image analysis and precise photometric calibration, we report a direct contrast ratio of 1 part in 100 million.

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The intrinsic nature of many astronomical objects, such as binary and multiple systems, exoplanets, circumstellar and debris disks, and quasar host galaxies, introduces challenging requirements for observational instrumentation and techniques. In each case, we encounter situations where the light from bright sources hampers our ability to detect surrounding fainter targets. To explore all features of such astronomical scenes, we must perform observations at the maximum possible contrast ratios. Charge-injection devices (CIDs) are capable of potentially exceeding contrast ratios of log 10 ( CR ) > 9 (i.e., 1 part in 1 billion) due to their unique readout architectures and inherent anti-blooming abilities. An on-sky testing of a commercially available CID, SpectraCAM XDR (SXDR), demonstrated raw contrast ratios from sub-optimal ground-based astronomical observations that imposed practical limits on the maximum achievable contrast ratios using CIDs. Here, we demonstrate the extreme contrast ratio imaging capabilities of the SXDR using observations of Sirius with the 1.0 m Jacobus Kapteyn Telescope, La Palma, Spain. Based on wavelet-based analysis and precise photometric and astrometric calibrations, we report a direct contrast ratio of Δm r = 18.54, log 10 ( CR ) = 7.41 ± 0.08 , or 1 part in 26 million. This is an order of magnitude higher compared to the previous CID results.