Hannah P. Earnshaw,1 Timothee Greffe,1 Roger M. Smith,1 Brian W. Grefenstette,1 Fiona A. Harrison,1 John J. Hennessy,1 Shouleh Nikzad,1 Charles A. Shapiro1
1California Institute of Technology (United States)
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.
We present an approach for improving the effective well depth of a CMOS detector for use on a UV space telescope by using a combination of two techniques: a dual-gain readout mode and the use of a multi-exposure HDR algorithm. Non-destructive readout of the detector in a high-gain and a low-gain mode optimizes the dynamic range of a single exposure by taking advantage of the low read noise of the first mode and the high well depth of the second. The dynamic range can be further extended by the addition of a second, shorter exposure to probe the saturated regions of the initial exposure. We find that, for simulations of an SRI CMOS imager we are testing, its initial sensitivity to ~3 orders of magnitude in flux can be improved to a dynamic range of over 5.5 orders of magnitude (equivalent to a difference of ~14 AB magnitudes) by the combination of a 300 second dual-gain exposure and a 3 second low-gain exposure, with a low overhead in additional read time and computational complexity.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.
The alert did not successfully save. Please try again later.
Hannah P. Earnshaw, Timothee Greffe, Roger M. Smith, Brian W. Grefenstette, Fiona A. Harrison, John J. Hennessy, Shouleh Nikzad, Charles A. Shapiro, "High dynamic range techniques for astronomical applications of CMOS devices," Proc. SPIE 12191, X-Ray, Optical, and Infrared Detectors for Astronomy X, 121910G (29 August 2022); https://doi.org/10.1117/12.2630367