FY2010 - Oak Ridge National Laboratory

Seed Money Fund—
Measurement Science and Systems Engineering Division
Mission Relevance
The value of dual waveband infrared cameras is particularly apparent under low ambient lighting
conditions, or when a target or individual is camouflaged or hidden in the surrounding environment, such
as in perimeter security situations. Under these conditions, potential targets and individuals are not easily
recognizable using either visible of infrared imaging techniques separately, but the combined images give
a clearer image of the potential target and surrounding threats. Since this device images thermal
signatures, there are many energy conservation applications, such as building heat loss and manufacturing
process controls, where heat loss can be monitored and controlled. Research and development of dual
wavelength infrared imagers is an active research area with funding from the Department of Defense.
These dual wavelength imagers can be used for rifle sights, vehicle navigation, perimeter security, ground
and aerial reconnaissance, and other night vision applications. The Defense Advanced Research Projects
Agency and the Army’s Night Vision Labs are actively funding R&D on innovative dual wavelength
imaging techniques to achieve their missions. Present imagers use two separate cameras that are bulky,
power and computer processing hungry, and expensive.
Results and Accomplishments
The following research tasks were performed on this project during FY 2010 to demonstrate the unique
advantages of the present dual wavelength imaging technique and to show the feasibility of the approach.
The FY 2010 tasks focused primarily on fabrication and testing of small bimorph pixel arrays and
optimization of their optical and structural parameters using finite element analysis (FEA). Our optical
modeling using the finite difference time domain method allowed us to identify geometries and optical
thicknesses of pixel elements that enhance conversion of thermally induced pixel deformations into
modulation of the optical intensity in the visible. Results of our thermal and mechanical FEA modeling
indicated in favor of cantilever versus bridge bimorph structures. Arrays of thermally sensitive bimorphs
that are transparent in the visible and absorbing in the infrared were demonstrated. The photon tunneling
test rig constructed in the initial (FY 2009) stage of the project was used to evaluate overall functionality
and to quantify performance of the fabricated pixel arrays. Two array formats, 1 10 and 20 30, were
used in these tests. Achieved figures of merit include temperature responsivity of 1.2 m/K and estimated
noise equivalent temperature difference of approximately 100 mK. The latter figure of merit indicates a
level of performance comparable to that of conventional, single waveband, uncooled infrared imagers.
Therefore, we have demonstrated a viable technology of a dual waveband imager particularly suitable for
applications in rifle sights, nighttime vehicle navigation, surveillance, and aerial reconnaissance.
05853
Nanomechanical Oscillators for Ultrasensitive Electric and
Electromagnetic Field Detection
Panos Datskos, Slobodan Rajic, Nickolay V. Lavrik, and Thomas Thundat
Project Description
Our proposed effort seeks to demonstrate the feasibility of using micro/nanomechanical oscillators to
detect electric and electromagnetic fields. Time varying electric field sensing is usually achieved using an
antenna and receiver. However, these antenna-based approaches do not exhibit high sensitivity over a
broad frequency (or wavelength) range. An important aspect of the project is that, in contrast to traditional
antennas, the dimensions of these nanomechanical oscillators are much smaller than the wavelength of the
electromagnetic wave. In our approach the detection of static electric fields and/or time varying electric
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