In imaging systems, whether visible or infrared, the pixel dimension plays a crucial role in determining critical system attributes such as size, weight, and Power (SWaP). Smaller pixels enhance the value proposition of the imager through reduced cost Focal Plane Arrays (FPAs) and/or added system functionality for a given spatial footprint. For systems that operate at temperatures in which FPA cold shield efficiency is relevant an additional benefit to performance is achieved with the faster optics mandated by use of small pixels. Ultimate pixel dimensions are limited by diffraction effects from the aperture and are in turn wavelength dependent. Limits to the reduction in pixel dimensions will be explored and related to the historical trends in system design with accompanying performance attributes. Key challenges in realizing ultimate pixel dimensions in focal plane array design will be discussed. Progress toward these limits at DRS will be reviewed for LWIR HgCdTe Focal Plane arrays fabricated with 5 micron pixel dimensions. Possible system implications tied to the success of these shrinking pixel FPAs will be postulated.

Date Published: 21 May 2014
PDF: 9 pages
Proc. SPIE 9100, Image Sensing Technologies: Materials, Devices, Systems, and Applications, 91000I (21 May 2014); doi: 10.1117/12.2054452

Published in SPIE Proceedings Vol. 9100:
Image Sensing Technologies: Materials, Devices, Systems, and Applications
Nibir K. Dhar; Achyut K. Dutta, Editor(s)