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.
is PDF file contains the front matter associated with SPIE Proceedings Volume 7319, including the Title Page, Copyright information, Table of Contents, Introduction, and the Conference Committee listing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
In spite of the fact that the original Raman microscope was designed in the early 1970's for Raman imaging,
wide-spread practical use of the technology did not appear until the last 5 years. The instruments are smaller,
faster, easier-to-use, promoting reports of a variety of interesting applications in fields as diverse as
nanomaterials, pharmaceuticals, composites, semiconductors, bio-clinical studies, polymers, ceramics and
glasses. While the information content in Raman analysis is quite high, the time to acquire an image has been
a deterrent to its application. Recent innovations including Swift and DUO Scan have addressed and are
addressing these issues. SWIFT (Scanning with Incredibly Fast Times) is a rapid CCD read-out technique
that is based on the synchronization between the XY motion of the motorized or piezo stage and the CCD
readout. DUO scanning uses a set of scanning mirrors above the microscope objective to raster rapidly the
laser beam across a sample area. This can be used to create a "giant pixel" in the map without compromising
the NA of the light collection, or to create a map with step sizes as small as 10nm. Swift, in combination with
DUO scan, as been used to produce full spectral maps of pharmaceutical tablets in times as short as 10
minutes, something that was previously believed to be near impossible. Off-line analysis of such a map using
multivariate techniques produces Raman images indicating the quality of component mixing, and also the
presence of minor, difficult-to-detect components (such as Mgstearate in pharmaceutical tablets).
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The Air Force Institute of Technology (AFIT) has built a rotating prism chromotomographic hyperspectral imager (CTI)
with the goal of extending the technology to exploit spatially extended sources with quickly varying (> 10 Hz)
phenomenology, such as bomb detonations and muzzle flashes. This technology collects successive frames of 2-D data
dispersed at different angles multiplexing spatial and spectral information which can then be used to reconstruct any
arbitrary spectral plane(s). In this paper, the design of the AFIT instrument is described and then tested against a spectral
target with near point source spatial characteristics to measure spectral and spatial resolution. It will be shown that, in
theory, the spectral and spatial resolution in the 3-D spectral image cube is the nearly the same as a simple prism
spectrograph with the same design. However, error in the knowledge of the prism linear dispersion at the detector array
as a function of wavelength and projection angle will degrade resolution without further corrections. With minimal
correction for error and use of a simple shift-and-add reconstruction algorithm, the CTI is able to produce a spatial
resolution of about 2 mm in the object plane (234 μrad IFOV) and is limited by chromatic aberration. A spectral
resolution of less than 1nm at shorter wavelengths is shown, limited primarily by prism dispersion.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We present a novel hyperspectral imaging technique based on tunable laser technology. By replacing the broadband
source and tunable filters of a typical NIR imaging instrument, several advantages are realized, including: high spectral
resolution, highly variable field-of-views, fast scan-rates, high signal-to-noise ratio, and the ability to use optical fiber
for efficient and flexible sample illumination. With this technique, high-resolution, calibrated hyperspectral images over
the NIR range can be acquired in seconds. The performance of system features will be demonstrated on two example
applications: detecting melamine contamination in wheat gluten and separating bovine protein from wheat protein in
cattle feed.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Hyperspectral reflectance imaging in the visible and NIR spectral ranges has considerable utility for revealing spatial
and chemical complexity in both biological systems and manufactured products. Conventional imaging systems are
based on broad-band illumination in tandem with a spectrometer or tunable filter placed between the sample and the
detector. These systems are typically slow (require seconds of integration per wavelength step), and the CW broad-band
source can cause significant heating of the sample. An alternative method is to use a tunable, pulsed, high-peak-power
(low average power) source coupled with a broad-band detector. This approach offers a reduction in data acquisition
time, the inherent ability to stop motion, and data collection at ambient temperature. An integrated system based on a 5-
ns pulsed laser tunable from 430 nm to 2150 nm has been used to obtain hyperspectral images in both the visible and
NIR spectral ranges. A number of camera/lens options allow for varied spectral bandwidths and the FOV, ranging from
11 × 15 mm2 to 15 × 20 cm2. An entire hyperspectral image stack can be collected in as little as 20 s. This method,
allowing fast, room-temperature data acquisition, has sufficient sensitivity to produce data that can be successfully
processed using spectral derivatives and multivariate analysis. We discuss several applications, both in vivo and
otherwise, of this alternative approach to visible/NIR hyperspectral imaging.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Performance studies and instrument designs for hyperspectral pushbroom imagers in thermal wavelength region are
introduced. The studies involve imaging systems based on both MCT and microbolometer detector. All the systems
employ pushbroom imaging spectrograph with transmission grating and on-axis optics. The aim of the work was to
design high performance instruments with good image quality and compact size for various application requirements.
A big challenge in realizing these goals without considerable cooling of the whole instrument is to control the instrument
radiation from all the surfaces of the instrument itself. This challenge is even bigger in hyperspectral instruments, where
the optical power from the target is spread spectrally over tens of pixels, but the instrument radiation is not dispersed.
Without any suppression, the instrument radiation can overwhelm the radiation from the target by 1000 times.
In the first imager design, BMC-technique (background monitoring on-chip), background suppression and temperature
stabilization have been combined with cryo-cooled MCT-detector. The performance of a very compact hyperspectral
imager with 84 spectral bands and 384 spatial samples has been studied and NESR of 18 mW/(m2srμm) at 10 μm
wavelength for 300 K target has been achieved. This leads to SNR of 580. These results are based on a simulation
model.
The second version of the imager with an uncooled microbolometer detector and optics in ambient temperature aims at
imaging targets at higher temperatures or with illumination. Heater rods with ellipsoidal reflectors can be used to
illuminate the swath line of the hyperspectral imager on a target or sample, like drill core in mineralogical analysis.
Performance characteristics for microbolometer version have been experimentally verified.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
A fast-scanning, high-resolution FTIR spectroradiometer has been designed and built for use in remote sensing, stand-off
detection, and spectral-temporal characterization of fast, energetic infrared events. The instrument design uses a
Michelson-type interferometer with a rotary modulator which is capable of continuous measurement of infrared spectra
at a rate of 1000 scans per second with 4 cm-1 resolution in the 2 - 25 micron spectral range. Sensitivity, spectral
accuracy, and radiometric precision are discussed along with specific design parameters. This instrument can be used
for passive sensing as a stand-alone sensor, or for active sensing as a receiver when used in conjunction with a highenergy
excitation source such as a laser. Applications include muzzle flash signature measurement, ordnance detonation
characterization, missile plume identification, and rocket motor combustion diagnostics.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Both the power and the challenge of hyperspectral technologies is the very large amount of data produced by spectral
cameras. While off-line methodologies allow the collection of gigabytes of data, extended data analysis sessions are
required to convert the data into useful information. In contrast, real-time monitoring, such as on-line process control,
requires that compression of spectral data and analysis occur at a sustained full camera data rate. Efficient, high-speed
practical methods for calibration and prediction are therefore sought to optimize the value of hyperspectral imaging.
A novel method of matched filtering known as science based multivariate calibration (SBC) was developed for
hyperspectral calibration. Classical (MLR) and inverse (PLS, PCR) methods are combined by spectroscopically
measuring the spectral "signal" and by statistically estimating the spectral "noise." The accuracy of the inverse model is
thus combined with the easy interpretability of the classical model. The SBC method is optimized for hyperspectral data
in the Hyper-CalTM software used for the present work. The prediction algorithms can then be downloaded into a
dedicated FPGA based High-Speed Prediction EngineTM module. Spectral pretreatments and calibration coefficients are
stored on interchangeable SD memory cards, and predicted compositions are produced on a USB interface at real-time
camera output rates. Applications include minerals, pharmaceuticals, food processing and remote sensing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Spectroscopic chemical identification is fundamentally a classification task where sensor measurements are compared
to a library of known compounds with the hope of determining an unambiguous match. When the
measurement signal-to-noise ratio (SNR) is very low (e.g. from short exposure times, weak analyte signatures,
etc.), classification can become very challenging, requiring a multiple-measurement framework such as sequential
hypothesis testing, and dramatically extending the time required to classify the sample. There are a wide variety
of defense, security, and medical applications where rapid identification is essential, and hence such delays are
disastrous. In this paper, we discuss an approach for adaptive spectroscopic detection where the introduction
of a tunable spectral filter enables the system to measure the projection of the sample spectrum along arbitrary
bases in the spectral domain. The net effect is a significant reduction in time-to-decision in low SNR cases. We
describe the general operation of such an instrument, present results from initial simulations, and report on our
experimental progress.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The rapid and sensitive identification of biological species is a critical need for the 1st responder and military
communities. Raman spectroscopy is a powerful tool for substance identification that has gained popularity with the
respective communities due to the increasing availability of portable Raman spectrometers. Attempts to use Raman
spectroscopy for the direct identification of biological pathogens has been hindered by the complexity of the generated
Raman spectrum. We report here the use of a sandwich immunoassay containing antibody modified magnetic beads to
capture and concentrate target analytes in solution and Surface Enhanced Raman Spectroscopy (SERS) tags conjugated
with these same antibodies for specific detection. Using this approach, the biological complexity of a microorganism can
be translated into chemical simplicity and Raman can be used for the identification of biological pathogens. The
developed assay has a low limit of detection due to the SERS effect, robust to commonly found white powders
interferants, and stable at room temperature over extended period of time. This assay is being implemented into a user-friendly
interface to be used in conjunction with the GE Homeland Protection StreetLab MobileTM Raman instrument for
rapid, field deployable chemical and biological identification.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We have designed and constructed a coded aperture spectrometer for use in the deep UV range. The Czerny-Turner design provides sufficient spectral resolution to observe Raman scattering features, while the use of a coded aperture provides a greatly improved light collection efficiency for scattering sources. The resulting instrument
is capable of analyzing Raman spectra from samples at a 1 meter viewing distance. We provide an overview of the system, its optical design, and some preliminary measurements.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Recent advances in the design of compact interferometers and infrared sampling accessories have allowed FTIR
spectroscopy to be taken out of the laboratory and into the field. The chemical identification capability of mid-infrared
spectroscopy has filled many needs of military, security, and emergency response personnel. Further design optimization
has led to the development of a hand-held FTIR system, the HazmatID Ranger, which enables new applications in
chemical identification and offers increased flexibility for elusive samples encountered in the field. An overview of the
performance of the HazmatID Ranger using a receiver operating characteristic analysis is presented along with a
discussion of the viability of hand-held FTIR measurements for applications in defense and security.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Recent advances in commercially available quantum cascade semiconductor materials providing laser gain in the 3-
12μm regime have been developed. This enables wavelength tunable, narrow linewidth external cavity quantum cascade
laser (ECqcL) sources operating above room temperature to be realized with high yield. Daylight has combined these
materials with advanced coating and attach technologies, mid-IR micro-optics and telecom-style packaging to yield
compact, hermetically-sealed lasers. In addition, ultra-broad tuning ranges (>250 wavenumbers) have been demonstrated
from a commercially available product platform. Meanwhile, phase continuous tuning capabilities have been achieved to
provide the ability to perform wavelength modulation spectroscopy in the mid-IR from similar commercial platforms.
When integrated and optimized with new room temperature mid-IR detectors and modern low power embedded digital
signal processing electronics, the resulting sensor platform can provide significant advantages. These include multispecies
fingerprint identification at real-time update rates (10 Hz). Daylight will review the most recent progress in
ECqcL devices as well as describe their portable, battery-operated Swept SensorTM technology based upon this platform.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
A MEMS (micro electro mechanical system) technology has been used to produce scanning grating chips which have a
tiltable plate with grating structures optimized for the 900nm ... 2500nm range as diffractive element. Based on these
chips different spectrometers and a hyper spectral imager have been realized for NIR-spectroscopic applications like
agricultural quality analysis, recycling and process control. Ongoing developments aim at the further reduction of size
and effort. Chip scale or wafer scale packaging technologies could help to shrink the complete spectroscopic system. The
integration of signal processing and evaluation routines opens new applications for a broad range of scientific and nonscientific
users.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
In this paper we present a novel translatory MOEMS device with extraordinary large stroke especially designed for fast
optical path modulation in an improved miniaturized Fourier-transform infrared (FTIR) spectrometer capable to perform
time resolved measurements from NIR to MIR. Recently, we presented a first MOEMS based FTIR system using a
different translatory MOEMS actuator with bending suspensions of the mirror plate and ±100μm oscillation amplitude
resulting in a limited spectral resolution of 30 cm-1.
For the novel MOEMS actuator an advanced pantograph suspension of the mirror plate was used to guarantee an
extraordinary large stroke of up to 500 μm required for an improved spectral resolution. To optimize the optical
throughput of the spectrometer the mirror aperture was increased to 7 mm2. The MOEMS actuators are driven electro
statically resonant using out-of-plane comb drives and operate at a resonant frequency of 500 (1000) Hz, respectively.
Hence, this enables to realize an improved MOEMS based FTIR-spectrometer with a spectral resolution of up to 10 cm-1,
a SNR of > 1000:1 and an acquisition time of 1 ms per spectrum of the miniaturized FTIR-system.
In this article we discuss in detail the design and the experimental characteristics of the novel large stroke translatory
MOEMS device. The application and system integration, especially the optical vacuum packaging, of this MOEMS
device in an improved miniaturized MOEMS based FTIR spectrometer enabling ultra rapid measurements in the NIRMIR
spectral region with 12cm-1 spectral resolution is discussed in a separate paper submitted to this conference.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We present an improved FTIR spectrometer using a novel MOEMS actuator and discuss in detail the properties of the
MOEMS component and the resulting FT-IR sensor device. Spectral resolution and the spectral range allow making use
of the inherent multi-analyte detection capabilities giving the spectroscopy platform an advantage over singlewavelength
IR sensors. With its further miniaturization potential due to its MOEMS core, this compact, energy efficient
and robust spectrometer can thus act as transducer for portable and ultra-lightweight spectroscopic IR sensors, e.g. all
purpose hazardous vapor sensors, sensors for spaceborne and Micro-UAV based IR analysis, and many more.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
This paper reports the design, fabrication, and characterization of a millimeter diameter, surface micromachined
Micro-Electro-Mechanical-Systems (MEMS) mirror, which is assembled perpendicular to the substrate and can be
linearly and repeatedly traversed through 600 μm. The moving mirror, when combined with a fixed mirror and
beamsplitter, make up a monolithic MEMS Michelson interferometer; all are made on the same substrate and in the
same surface micromachined fabrication process. The beamsplitter has been specifically designed such that the
motion of the mirror enables modulation of light over the 2-14 μm spectral region. The rapid scan MEMS
Michelson interferometer is the engine behind a miniaturized, Fourier transform infrared (FTIR) absorption
spectrometer. The FTIR measures the absorption of infrared (IR) radiation by a target material, which can be used
for the detection and identification of gases, liquids, or solids. The fabrication of the mirror with the ability to
displace 600 μm along the optical axis enables the miniaturized system to have species identification resolution,
while leveraging wafer scale batch fabrication to enable extremely low system cost. The successful fabrication of
the millimeter diameter mirrors and beamsplitter with interferometric alignment over the range of travel of the
moving mirror promises unprecedented sensitivity relative to the size of the FTIR spectrometer system.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
This paper reports work on the development of rugged micro-electromechanical systems (MEMS)-based
microspectrometers for real-time applications in agriculture. The devices are electrostatically actuated, first order Fabry-
Perot tuneable optical filters, hybridised with InGaAs photodiode detectors. Tuning range and resolution of the devices
are 1615 nm to 2425 nm and 52 nm (FWHM) at 2000 nm, respectively. To our knowledge, this tuning range is the
largest reported for a MEMS-based Fabry-Perot filter. Three-layer distributed Bragg reflectors are used for the Fabry-
Perot mirrors, and consist of e-beam evaporated layers of germanium - silicon monoxide - germanium. The moveable
mirror also includes two silicon nitride layers that act as the MEMS flexures, stress compensation layers, and as an
encapsulant for the mirror layers. The spectral resolution matches the theoretical expected for the mirror structures used
when the residual bowing of the mirror (~15 nm across a diameter of 70 μm) is included, and can be improved to ~10 nm
if five layer mirrors are used. The out of band rejection is approximately 20 dB. Experimental results show that the
throughput of the device is sufficient to allow transmittance, specular reflectance and diffuse reflectance spectra to be
measured. The primary outstanding issue is wavelength calibration, and is being addressed using a number of
approaches including incorporation of wavelength calibration standards in the hybrid structure and accurate, real-time
measurement of the separation of the two mirrors.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.