High-resolution amorphous silicon image sensor

Thorsten Graeve; Youming Li; Andrew Fabans; Wingo Huang

doi:10.1117/12.237811

11 April 1996 High-resolution amorphous silicon image sensor

Thorsten Graeve, Youming Li, Andrew Fabans, Wingo Huang

Proceedings Volume 2708, Medical Imaging 1996: Physics of Medical Imaging; (1996) https://doi.org/10.1117/12.237811
Event: Medical Imaging 1996, 1996, Newport Beach, CA, United States

Abstract

This paper describes a new prototype a-Si (amorphous silicon) x-ray image sensor developed at EG&G Reticon. The sensor consists of a 512 by 512 array of a-Si photodiodes placed on 100 micrometer centers. The active area measures 5 cm on a side. Each pixel is addressed by a pair of switching diodes rather than the more common TFT (thin film transistor) switch. This approach leads to a simplified all-diode design with excellent fill factor, large dynamic range and good performance. The sensor is intended primarily for high-resolution x-ray imaging applications. A scintillator in direct contact with the diode array is used to convert incident x-ray photons to visible light detectable by the a-Si photodiodes. Since the conversion takes place directly at the sensor surface, no bulky intermediate optics are needed. The entire sensor plus support electronics can be mounted in a package less than 3 cm thick. The paper describes the sensor performance in terms of dark current, image lag, sensitivity and dynamic range. The MTF of the sensor and attached scintillator is measured by exposing the device through a narrow slit illuminated by a 50 kV x-ray source. Good contrast and sensitivity are achieved even at the Nyquist limit of the sensor resolution. Several images demonstrating the resolution and sensitivity of the sensor are presented.

Citation Download Citation

Thorsten Graeve, Youming Li, Andrew Fabans, and Wingo Huang "High-resolution amorphous silicon image sensor", Proc. SPIE 2708, Medical Imaging 1996: Physics of Medical Imaging, (11 April 1996); https://doi.org/10.1117/12.237811

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