Teledyne Judson Technologies (TJT) has been developing technology for small pixel, large format, low dark current, and
low capacitance NIR/SWIR InGaAs detector arrays, aiming to produce <10μm pixels and >2Kx2K format arrays that
can be operated at or near room temperature. Furthermore, TJT is now developing technology for sub-10μm pixel arrays
in response to requirements for a variety of low light level (LLL) imaging applications. In this paper, we will review test
data that demonstrates lower dark current density for 10-20μm pixel arrays. We will present preliminary results on the
successful fabrication of test arrays with pixels as small as 5μm. In addition, a lot of effort has been made to control and
reduce the detector pixel capacitance which can become another source of detector noise. TJT is also developing 4"
InGaAs wafer process and now offers four different types of InGaAs 2D arrays/FPAs that are tailored to different
customer requirements for dark current, capacitance, spectral response, and bias range.
The new NASA Enhanced MODIS Airborne Simulator (eMAS) is based on the legacy MAS system,
which has been used extensively in support of the NASA Earth Observing System program since
1995. eMAS consists of two separate instruments designed to fly together on the NASA ER-2 and
Global Hawk high altitude aircraft.
The eMAS-IR instrument is an upgraded version of the legacy MAS line-scanning spectrometer,
with 38 spectral bands in the wavelength range from 0.47 to 14.1 μm. The original LN2-cooled
MAS MWIR and LWIR spectrometers are replaced with a single vacuum-sealed, Stirling-cooled
assembly, having a single MWIR and twelve LWIR bands. This spectrometer module contains a
cold optical bench where both dispersive optics and detector arrays are maintained at cryogenic
temperatures to reduce infrared background noise, and ensure spectral stability during high altitude
The EMAS-HS instrument is a stand-alone push-broom imaging spectrometer, with 202 contiguous
spectral bands in the wavelength range from 0.38 to 2.40 μm. It consists of two Offner
spectrometers, mated to a 4-mirror anastigmatic telescope. The system has a single slit, and uses a
dichroic beam-splitter to divide the incoming energy between VNIR and SWIR focal plane arrays.
It will be synchronized and bore-sighted with the IR line-scanner, and includes an active source for
monitoring calibration stability.
eMAS is intended to support future satellite missions including the Hyperspectral Infrared Imager (
HyspIRI,) the National Polar-orbiting Operational Environmental Satellite System (NPOESS)
Preparatory Project (NPP,) and the follow-on Joint Polar Satellite System (JPSS.)