Higher definition mid-wave infrared scene projectors via shrinking pixel pitch
Date
2020
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
The role an infrared scene projector (IRSP) plays in the qualication of infrared
(IR) detection systems is to provide realistic simulated scenarios in a lab setting. As
IR sensors become ever increasingly complex, there comes a critical need for projec-
tion technologies to provide a means of testing. This method of hardware in the
loop (HWIL) implementation reduces the cost and time of development. As a result,
research and development (R&D) groups in industry and the military have a large
interest in IRSP technologies. The IRSP technology to be discussed uses light emitting
diodes (LED) to produce mid-wave infrared (MWIR) signatures. Going forward, IRSP
systems need even higher resolutions coincident with increased projection speeds. A
new read-in integrated circuit (RIIC) architecture is necessary to push this technology
forward towards these higher resolutions. Using various very-large scale integration
(VLSI) techniques, the new RIIC architecture is designed to be modular and scalable
for emitters with dierent characteristics. The new RIIC architecture has be designed
using the ONC18 process from OnSemiconductor. The base pixel has been made 4X
smaller than the current state of the art RIICs for LED-based IRSPs. The principal
reason for exploring a smaller pitch has been to test the theory of better light ex-
traction from the Super-lattice LED (SLED) arrays. The SLED pixel is grown on a
gallium-antimonide (GaSb) wafer using a cascade approach that increases aggregate
light output. The RIIC pixel has been characterized using a testing platform that
provides the digital patterns needed to drive the static logic, and the IV characteris-
tics of every pixel were collected using a Keithley 24XX meter. The SLED pixel has
been characterized using an indium-antimonide (InSb) detector. LIV curves have been
generated to compare variable size parts. Hybridization of the prototype part has not
been performed, however, controlling the SLED pixel with the RIIC pixel has been
demonstrated. LIV curves for these experiments were collected via the Keithley meter
in conjunction with a forward-looking-infrared (FLIR) 6800 camera.
Description
Keywords
Mid-wave infrared signatures, Projection, Read-in integrated circuits, Super-lattice LED, Light emitting diodes, Infrared sensor testing, Method of hardware in the loop, Resolution, Projection speed, Very-large scale integration, Modular, Scalable