Extended dynamic range CMOS active pixel architecture for x-ray detectors

Willy H. Maes; Olivier Tousignant; Ruud J. M. Vullers; Yves Kessener; James J. Miller; Inge M. Peters

doi:10.1117/12.2549236

16 March 2020 Extended dynamic range CMOS active pixel architecture for x-ray detectors

Willy H. Maes, Olivier Tousignant, Ruud J. M. Vullers, Yves Kessener, James J. Miller, Inge M. Peters

Proceedings Volume 11312, Medical Imaging 2020: Physics of Medical Imaging; 113123Z (2020) https://doi.org/10.1117/12.2549236
Event: SPIE Medical Imaging, 2020, Houston, Texas, United States

Abstract

X-ray detectors increasingly utilize active pixel CMOS instead of amorphous silicon technology because of its superior noise, pixel lag, readout speed and offset stability. We already demonstrated [1] that adding an a additional pixel capacitance to a standard 3T CMOS pixel architecture allows operating the detector in either high sensitivity (HS) or high saturation dose (HD) mode. Since the charge capacity is limited in HS mode, a large signal will saturate the pixel, causing a loss of information. In HD mode, a very low exposure will lead to a loss of contrast-to-noise ratio (CNR) due to the inherently higher noise floor in this mode. Using the same 3T pixel architecture, we propose a dual readout method to combine the benefits of HS and HD modes. After a single exposure the pixel signal is read twice, respectively in HS and HD mode. The two linear signal values are then combined to create the pixel value of the final image. In this paper proof of concept is demonstrated using images acquired separately and combined offline. The benefits of this method are demonstrated for different x-ray imaging modalities such as mammography, extra-oral dental, interventional and non-destructive testing. Using different detector models, results show that extended dynamic range combined with low noise leads to better image quality without introducing artifacts. It is expected that implementing the fast CMOS-sensor dual readout and image synthesis inside the detector will preserve important application requirements such as frame rate, data bandwidth and power consumption.

Citation Download Citation

Willy H. Maes, Olivier Tousignant, Ruud J. M. Vullers, Yves Kessener, James J. Miller, and Inge M. Peters "Extended dynamic range CMOS active pixel architecture for x-ray detectors", Proc. SPIE 11312, Medical Imaging 2020: Physics of Medical Imaging, 113123Z (16 March 2020); https://doi.org/10.1117/12.2549236

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

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.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
9 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Sensors

X-rays

X-ray detectors

X-ray imaging

Image quality

CMOS sensors

Switches

Show All Keywords

Keywords/Phrases

Search In:

Publication Years