Mr. Dakota McKeown Profile

Dakota McKeown

SPIE Involvement:

Author

Publications (1)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 9 March 2018 Paper

Cascaded systems analysis of photon-counting field-shaping multi-well avalanche detectors (SWADs)

Jesse Tanguay, Jann Stavro, Dakota McKeown, Amir Goldan, Ian Cunningham, Wei Zhao

Proceedings Volume 10573, 105734V (2018) https://doi.org/10.1117/12.2293348

KEYWORDS: Sensors, Modulation transfer functions, X-rays, Monte Carlo methods, X-ray detectors, Systems modeling, Quantum efficiency, X-ray imaging, Spatial resolution, Imaging systems, Photon counting, Photon counting theory

Read Abstract +

Single-photon-counting (SPC) x-ray detectors are expected to play a key role in the next generation of medical x-ray imaging. The spatial resolution of SPC x-ray detectors is an important design criterion, in particular for mammography in which one of the primary aims is to detect and differentiate micro-calcifications. The purpose of this abstract is to extend the cascaded systems approach to investigate the influence of reabsorption of characteristic x rays on SPC spatial resolution. A parallel-cascaded model is used to describe reabsorption of characteristic x rays following photoelectric interactions. We use our model to calculate the large-area gain and modulation transfer function (MTF) of amorphous selenium (a-Se) SPC detectors that use a field-Shaping multi-Well Avalanche Detector (SWAD) structure to overcome the low conversion gain of a-Se. Our model accounts for emission and reabsorption of characteristic x rays, x-ray conversion to electron-hole pairs, avalanche gain and gain variance, integration of secondary quanta in detector elements, electronic noise, and energy threshold. Theoretical predictions are compared with the results of Monte Carlo simulations. Our analysis shows that under mammographic imaging conditions, the a-Se/SWAD structure with an avalanche gain of 10 or greater results in minimal loss of photon counts below the electronic noise floor for electronic noise levels ~500 - 700 e-h pairs. Double counting of characteristic x-rays inflates the large-area gain by ~20% relative to the quantum efficiency, and results in modest MTF degradation relative to energy-integrating systems. Excellent agreement between theoretical and Monte Carlo analyses was observed. This approach provides a theoretical framework for understanding SPC detector performance and for system optimization

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

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:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years