This work presents the design, development, and testing of a field portable imaging spectropolarimeter that operates over the short-wavelength and middle-wavelength portion of the infrared spectrum. The sensor includes a pair of sapphire Wollaston prisms and several high order retarders to produce the first infrared implementation of an imaging Fourier transform spectropolarimeter, providing for the measurement of the complete spectropolarimetric datacube over the passband. The Wollaston prisms serve as a birefringent interferometer with reduced sensitivity to vibration when compared to an unequal path interferometer, such as a Michelson. Polarimetric data are acquired through the use of channeled spectropolarimetry to modulate the spectrum with the Stokes parameter information. The collected interferogram is Fourier filtered and reconstructed to recover the spatially and spectrally varying Stokes vector data across the image.The intent of this dissertation is to provide the reader with a detailed understanding of the steps involved in the development of this infrared hyperspectral imaging polarimeter (IHIP) instrument. First, Chapter 1 provides an overview of the fundamental concepts relevant to this research. These include imaging spectrometers, polarimeters, and spectropolarimeters. A detailed discussion of channeled spectropolarimetry, including a historical study of previous implementations, is also presented. Next a few of the design alternatives that are possible for this work are outlined and discussed in Chapter 2. The configuration that was selected for the IHIP is then presented in detail, including the optical layout, design, and operation. Chapter 3 then presents an artifact reduction technique (ART) that was developed to improve the IHIP's spectropolarimetric reconstructions by reducing errors associated with non-band-limited spectral features. ART is experimentally verified in the infrared using a commercial Fourier transform spectrometer in combination with Yttrium Vanadate as well as Cadmium Sulfide retarders.The remainder of this dissertation then details the testing and analysis of the IHIP instrument. Implementation of ART with the IHIP as well as the employed calibration techniques are described in Chapter 4. Complete calibration of the IHIP includes three distinct processes to provide radiometric, spectral, and polarimetric calibration. With the instrument assembled and calibrated, results and error analyses are presented in Chapter 5. Spectropolarimetric results are obtained in the laboratory as well as outdoors to test the IHIP's real world functionality. The performance of the instrument is also assessed, including experimental measurement of signal-to-noise ratio (SNR), and an analysis of the potential sources of systematic error (such as retarder misalignment and finite polarizer extinction ratio). Chapter 6 presents the design and experimental results for a variable Wollaston prism that can be added to the IHIP to vary the fringe contrast across the field of view. Finally, Chapter 7 includes brief closing remarks summarizing this work and a few observations which may be useful for future infrared imaging Fourier transform channeled spectropolarimeter instruments.

<p>In the last several years, there has been an increased focus on connecting image processing and artificial intelligence. Especially in the field of medical image diagnostics the benefits for such integration is apparent. In this paper we present use of the Common Object Request Broker Architecture (CORBA), as the mean for connecting existing systems for image processing and artificial intelligence. To visualize this, we will use CORBA for connecting Dynamic Imager and JavaCreek. Dynamic Imager is an image processing software, that is especially suitable for setting up and test customized sequences of image processing operations. JavaCreek is an artificial intelligence software based on the Case-Based Reasoning (CBR) theory.</p><p>After connecting the two systems with CORBA, we proceed develop the specific image processing methods for data gathering, and a knowledge base for diagnosis in the artificial intelligence system. The image processing methods and the knowledge base are produced for one special knowledge domain, for visualizing how the proposed system can help in medical image diagnostics.</p><p>The task we use to visualize our approach, is detecting malignancy in breast tumors, from magnetic resonance (MR) images taken over time as contrast agents is injected. This is from a reasonably new method for deciding if a tumor is malignant or benign. All image processing methods and the knowledge base is produced to let the two systems cooperate to find and diagnose tumors.</p><p>The image processing methods, the knowledge model, and the selected software with CORBA connection, was the basis for our system implementation. The implementation was tested with data gathered during the development of the clinical method for determining if a tumor is malignant, from the MR images. In all 127 patient cases was available, where 77 has malignant tumors in the gathered images. The results was then compared with diagnosis methods based on manual detection, and on other image processing methods. Although the found results were promising, there was also found several areas for future work.</p>

In the last several years, there has been an increased focus on connecting image processing and artificial intelligence. Especially in the field of medical image diagnostics the benefits for such integration is apparent. In this paper we present use of the Common Object Request Broker Architecture (CORBA), as the mean for connecting existing systems for image processing and artificial intelligence. To visualize this, we will use CORBA for connecting Dynamic Imager and JavaCreek. Dynamic Imager is an image processing software, that is especially suitable for setting up and test customized sequences of image processing operations. JavaCreek is an artificial intelligence software based on the Case-Based Reasoning (CBR) theory. After connecting the two systems with CORBA, we proceed develop the specific image processing methods for data gathering, and a knowledge base for diagnosis in the artificial intelligence system. The image processing methods and the knowledge base are produced for one special knowledge domain, for visualizing how the proposed system can help in medical image diagnostics. The task we use to visualize our approach, is detecting malignancy in breast tumors, from magnetic resonance (MR) images taken over time as contrast agents is injected. This is from a reasonably new method for deciding if a tumor is malignant or benign. All image processing methods and the knowledge base is produced to let the two systems cooperate to find and diagnose tumors. The image processing methods, the knowledge model, and the selected software with CORBA connection, was the basis for our system implementation. The implementation was tested with data gathered during the development of the clinical method for determining if a tumor is malignant, from the MR images. In all 127 patient cases was available, where 77 has malignant tumors in the gathered images. The results was then compared with diagnosis methods based on manual detection, and on other image processing methods. Although the found results were promising, there was also found several areas for future work.

Thin film transistor (TFT) backplanes are being continuously researched for new applications such as active-matrix organic light emitting diode (AMOLED) displays, sensors, and x-ray imagers. However, the circuits implemented in presently available fabrication technologies including poly silicon (poly-Si), hydrogenated amorphous silicon (a-Si:H), and organic semiconductor, are prone to spatial and/or temporal non-uniformities. While current-programmed active matrix (AM) can tolerate mismatches and non-uniformity caused by aging, the long settling time is a significant limitation. Consequently, acceleration schemes are needed and are proposed to reduce the settling time to 20 µs. This technique is used in the development of a pixel circuit and system for biomedical imager and sensor. Here, a metal-insulator-semiconductor (MIS) capacitor is adopted for adjustment and boost of the circuit gain. Thus, the new pixel architecture supports multi-modality imaging for a wide range of applications with various input signal intensities. Also, for applications with lower current levels, a fast current-mode line driver is developed based on positive feedback which controls the effect of the parasitic capacitance. The measured settling time of a conventional current source is around 2 ms for a 100-nA input current and 200-pF parasitic capacitance whereas it is less than 4 μs for the driver presented here. For displays needed in mobile devices such as cell phones and DVD players, another new driving scheme is devised that provides for a high temporal stability, low-power consumption, high tolerance of temperature variations, and high resolution. The performance of the new driving scheme is demonstrated in a 9-inch fabricated display intended for DVD players. Also, a multi-modal imager pixel circuit is developed using this technique to provide for gain-adjustment capability. Here, the readout operation is not destructive, enabling the use of low-cost readout circuitry and noise reduction techniques. In addition, a highly stable and reliable driving scheme, based on step calibration is introduced for high precision displays and imagers. This scheme takes advantage of the slow aging of the electronics in the backplane to simplify the drive electronics. The other attractive features of this newly developed driving scheme are its simplicity, low-power consumption, and fast programming critical for implementation of large-area and high-resolution active matrix arrays for high precision.

Thin film transistor (TFT) backplanes are being continuously researched for new applications such as active-matrix organic light emitting diode (AMOLED) displays, sensors, and x-ray imagers. However, the circuits implemented in presently available fabrication technologies including poly silicon (poly-Si), hydrogenated amorphous silicon (a-Si:H), and organic semiconductor, are prone to spatial and/or temporal non-uniformities. While current-programmed active matrix (AM) can tolerate mismatches and non-uniformity caused by aging, the long settling time is a significant limitation. Consequently, acceleration schemes are needed and are proposed to reduce the settling time to 20 µs. This technique is used in the development of a pixel circuit and system for biomedical imager and sensor. Here, a metal-insulator-semiconductor (MIS) capacitor is adopted for adjustment and boost of the circuit gain. Thus, the new pixel architecture supports multi-modality imaging for a wide range of applications with various input signal intensities. Also, for applications with lower current levels, a fast current-mode line driver is developed based on positive feedback which controls the effect of the parasitic capacitance. The measured settling time of a conventional current source is around 2 ms for a 100-nA input current and 200-pF parasitic capacitance whereas it is less than 4 μs for the driver presented here. For displays needed in mobile devices such as cell phones and DVD players, another new driving scheme is devised that provides for a high temporal stability, low-power consumption, high tolerance of temperature variations, and high resolution. The performance of the new driving scheme is demonstrated in a 9-inch fabricated display intended for DVD players. Also, a multi-modal imager pixel circuit is developed using this technique to provide for gain-adjustment capability. Here, the readout operation is not destructive, enabling the use of low-cost readout circuitry and noise reduction techniques. In addition, a highly stable and reliable driving scheme, based on step calibration is introduced for high precision displays and imagers. This scheme takes advantage of the slow aging of the electronics in the backplane to simplify the drive electronics. The other attractive features of this newly developed driving scheme are its simplicity, low-power consumption, and fast programming critical for implementation of large-area and high-resolution active matrix arrays for high precision.

CMOS imagers are replacing CCD imagers in many applications and will continue to make new applications possible. CMOS imaging offers lower cost implementations on standard CMOS processes which allow for mixed signal processing on-chip. A system-on-a-chip approach offers the ability to perform complex algorithms faster, in less space, and with lower power and noise. Our transform imager is an implementation of a mixed focal plane and peripheral computation imager which allows high fill factor with high computational rates at low power. However, in order to use the technology effectively a need to verify and further understand the behavior and of the pixel elements in this transform imager was needed. This thesis presents a study of the pixel elements and mismatches and errors in the pixel array of this imager. From there, a discussion about removing offsets and an implementation of a circuit to remove the largest offsets is shown. To further enhance performance, initial work to develop light adaptive readout circuits is presented. Finally, an overview is given of a newly designed one-megapixel transform imager with many design improvements.

There are many observational methods for studying debris disks because of constraints imposed on observing their predominately infrared wavelength emission close to the host star. Two methods which are discussed here are ground-based high contrast imaging and space-based far-IR emission. The Gemini Planet Imager (GPI) is a high contrast near-IR instrument designed to directly image planets and debris disks around other stars by suppressing star light to bring out faint sources nearby. Because debris disks are intrinsically polarized, polarimetry offers a useful way to enhance the scattered light from them while suppressing the diffracted, unpolarized noise. I discuss the characterization of GPI's microlens point spread function (PSF) in polarization mode to try to improve the quality of the processed data cubes. I also develop an improved flux extraction method which takes advantage of an empirically derived high-resolution PSF for both spectral and polarization modes. To address the instrumental effects of flexure, which affect data quality, I develop methods to counteract the effect by using the science images themselves without having to take additional calibrations. By reducing the number of calibrations, the Gemini Planet Imager Exoplanet Survey (GPIES) can stand to gain ~66 hours of additional on-sky time, which can lead to the discovery of more exoplanetary systems. The Herschel Space Observatory offers another method for observing debris disks which is ideally suited to measure the peak dust emission in the far-IR. Through a careful analysis, we look at 100/160 μm excess emission around λ Boo stars, to differentiate whether the emission is from a debris disk or a bowshock with the interstellar medium. It has been proposed that the stars' unusual surface abundances are due to external accretion of gas from those sources. We find that the 3/8 stars observed are well resolved debris disks and the remaining 5/8 were inconsistent with bowshocks. To provide a causal explanation of the phenomenon based on what we now know of their debris disks, I explore Poynting-Robertson (PR) drag as a mechanism for secondary accretion via a debris disk. However, I find that the accretion rates are too low to cause the surface abundance anomaly. Further study into the debris disks in relation to stellar abundances and surfaces are required to rule out or explain the λ Boo phenomenon through external accretion. / Graduate / 0606 / zhd@uvic.ca

Thesis (Ph.D.)--York University, 2006. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 181-195). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR19764

Recent discoveries in geospace science have necessitated the design of compact UV imaging instruments to make space-based observations from multiple vantage points. The miniaturized ultraviolet imager (MUVI) instrument from the Space Sciences Laboratory (SSL) at UC Berkeley is under development to facilitate such discoveries on a wider scale. This thesis documents the design, integration, and characterization of a vacuum compatible manipulator to calibrate the MUVI instrument inside the UV thermal vacuum chamber at SSL. Precision linear and rotation stages were implemented with custom mounting plates to achieve four degrees of freedom. Optical components were installed to imitate the MUVI instrument for testing purposes. A customized PCB was fabricated to control the stages and receive position feedback data. A Graphical User Interface was programmed and utilized to position the manipulator during experimental validation. Field of View sweeps were conducted using visible light and a monochromatic CMOS sensor to track the coordinates of a laser's centroid. An analytical model of the optics assembly was developed and later refined from the experimental results. Using this model, the translation stages successfully compensated for optical misalignments. Analysis of the performance data showed the pointing resolution of the manipulator was less than 1 arcmin, which satisfied the calibration requirement for the MUVI imager.

In this thesis is dealed the technical term diagnostic with Fluke Ti55 thermo imager. In the introduction of description is analyzed noncontact temperature measurement including principle, uncertainties measurement and measurement system. In other parts of the work is focused on thermal imaging, termogram, description Fluke Ti55 termo imager and measurement of mechanical stress. The concluding part of the description and processing of measurements, including their evaluation.