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1
Hedges, Sarah Jane. "Production and reliability aspects of the CCD mosaic for the SLD Vertex Detector." Thesis, Brunel University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305193.
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Ferguson, Terry Duane. "THE CHARACTERIZATION OF A VIRTUAL PHASE CCD IMAGER (DETECTORS)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/291601.
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Harris, Emma Jane. "Application of a novel CCD technology to medical imaging." Thesis, University College London (University of London), 2002. http://discovery.ucl.ac.uk/1317861/.
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This thesis describes an evaluation of a novel low light level charge couple device (L3CCD) technology. Two L3CCDs have been fully evaluated in terms of their signal and noise properties. The primary aim of this work is to identify the device characteristics that affect the overall performance. Conclusions have been made to this end and a prediction of the optimal performance in terms of the device sensitivity is made. Comparisons with other detectors suitable for use in medical imaging have shown that the L3CCD surpasses other detectors in specific performance characteristics and is comparable in others. The competitive performance of the L3CCD confirms that it may afford benefits in those areas in which the L3CCD has superior performance compared to other detectors. Two diagnostic imaging techniques which were identified as applications of L3CCD technology have been investigated. Linear systems analysis has been used to predict the performance of two L3CCD based imaging systems for use in fluoroscopic imaging. Comparison of the predicted performance of the two system with systems in clinical use show that an L3CCD coupled to an x-ray phosphor via a tapered fibre optic is a competitive alternative to present fluoroscopic imaging systems. Experimental validation of the model has confirmed this conclusion. An L3 detector has been designed, built and evaluated for diffraction enhanced breast imaging. To demonstrate the use of the L3 detector for diffraction enhanced breast imaging it has been used to acquire diffraction images of human breast tissue with cancerous inclusions. Measurements of scatter contrast confirm improvements in scatter contrast compared to transmission contrast. The successful demonstration of the L3CCDs ability to collect diagnostic information has shown that the L3CCD is suitable for diffraction enhanced breast imaging.
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Stevens, Eric G. "A low-noise CCD electrometer using buried-channel LDD NMOSFETs /." Online version of thesis, 1987. http://hdl.handle.net/1850/9018.
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Carter, DB. "Automation of the acquisition system of the 1,9 m telescope for the charge coupled device (CCD) camera." Thesis, Cape Technikon, 1988. http://hdl.handle.net/20.500.11838/1075.
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Thesis (Master Diploma (Electrical Engineering))-- Cape Technikon, Cape Town, 1988<br>This thesis describes the control system developed to improve the efficiency
of star acquisition on a ground-based optical telescope. "Star Acquisition" refers to the
process of identifying the star of interest in a field of stars and centering it on the optical
axis of the telescope , as well as setting an autoguider detector on a suitable star so the
autoguider can improve the tracking performance of the telescope. Efficiency is improved
by making all functions remote controlled , so the astronomer does not have to move
between the control room and the telescope to operate the instrument.
6
Zhao, Jing. "Design and evaluation of a screen-CCD imaging system for medical radiology /." Online version of thesis, 1992. http://hdl.handle.net/1850/11253.
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Li, Wai-Mo 1964. "Sensor modeling and image restoration for a CCD pushbroom imager." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276601.
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Following the development of detector technology, remote sensing image detection is being implemented with charge-coupled devices (CCD), which have promising features. The French SPOT system is the first civilian satellite sensor employing a CCD in its detection unit. In order to obtain the system transfer function (TF), a linear system model is developed in the across- and along-track directions. The overall system TF, including pixel sampling effects, is then used in the Wiener filter function to derive an optimal restoration function. A restoration line spread function (RLSF) is obtained by the inverse Fourier transform of the Wiener filter and multiplied with a window function. Simulation and empirical tests are described comparing the RLSF to standard kernels used for image resampling for geometric correction. The RLSF results in superior edge enhancement as expected.
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Hsieh, Long-Bing. "An EPROM based waveform generator for a CCD test station." Ohio : Ohio University, 1988. http://www.ohiolink.edu/etd/view.cgi?ohiou1182788524.
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Hachim, Abdallah. "Mesure de la vitesse de bouteilles sur un convoyeur par caméra CCD." Nancy 1, 1987. http://www.theses.fr/1987NAN10082.
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Greig, Thomas Alexander. "Development of CMOS active pixel sensors." Thesis, Brunel University, 2008. http://bura.brunel.ac.uk/handle/2438/5345.
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This thesis describes an investigation into the suitability of complementary metal oxide semiconductor (CMOS) active pixel sensor (APS) devices for scientific imaging applications. CMOS APS offer a number of advantages over the established charge-coupled device (CCD) technology, primarily in the areas of low power consumption, high-speed parallel readout and random (X-Y) addressing, increased system integration and improved radiation hardness. The investigation used a range of newly designed Test Structures in conjunction with a range of custom developed test equipment to characterise device performance. Initial experimental work highlighted the significant non-linearity in the charge conversion gain (responsivity) and found the read noise to be limited by the kTC component due to resetting of the pixel capacitance. The major experimental study investigated the contribution to dark signal due to hot-carrier injection effects from the in-pixel transistors during read-out and highlighted the importance of the contribution at low signal levels. The quantum efficiency (QE) and cross-talk were also investigated and found to be limited by the pixel fill factor and shallow depletion depth of the photodiode. The work has highlighted the need to design devices to explore the effects of individual components rather than stand-alone imaging devices and indicated further developments are required for APS technology to compete with the CCD for high-end scientific imaging applications. The main areas requiring development are in achieving backside illuminated, deep depletion devices with low dark signal and low noise sampling techniques.
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Leal, Michael J. "Effect of pixel size and scintillator on image quality of a CCD-based digital x-ray imaging system." Link to electronic thesis, 2001. http://www.wpi.edu/Pubs/ETD/Available/etd-0502101-123456.
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Zarif, Yussefian Nikta. "Mise en oeuvre d'un mode d'imagerie par transillumination et détection multi-vue à ultra-faible bruit dans l'imageur QOS[indice supérieur TM] pour imagerie moléculaire optique sur petit animal." Mémoire, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5891.
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La tomographie optique diffuse (TOD) est une technique d’imagerie médicale relativement
récente qui utilise la lumière dans le proche infrarouge pour acquérir des images in vivo
de façon non invasive. Cette technique est en utilisation croissante par de nombreux chercheurs et biologistes et plusieurs équipes dans le monde travaillent sur le développement de scanners par TOD y compris notre groupe de recherche (groupe TomOptUS).
Le Centre d’imagerie moléculaire de Sherbrooke dispose d’un appareil pour imagerie optique sur petit animal développé par la compagnie Quidd, soit le QOS (Quidd Optical
imaging System). Cet appareil est utilisé par des biologistes et chercheurs pour diverses
études précliniques sur modèles animaux (souris) de maladies humaines comme le cancer. Le QOS est entièrement contrôlé par ordinateur à l’aide d’un logiciel sophistiqué (le QOSoft) qui permet d’obtenir des images en fluorescence et en bioluminescence. Il est
toutefois limité en ne permettant d’acquérir que des images planaires de la lumière sortant
d’un animal ; il ne permet pas la tomographie, à savoir obtenir des images tridimensionnelles (3D) des sources fluorescentes ou bioluminescentes situées en profondeur à l’intérieur de l’animal. Bien que le QOS offre une grande flexibilité en terme d’angle d’acquisition d’images autour de l’animal avec sa caméra montée sur un bras rotatif, il a une sensibilité limitée pour de l’imagerie en profondeur, notamment parce qu’il fonctionne en mode épiillumination (détection de la lumière du même côté que l’injection de la lumière excitatrice
dans l’animal) et aussi à cause de la sensibilité limitée de sa caméra.
Afin d’augmenter les capacités tomographiques et la sensibilité du QOS, ainsi que le
contraste des images qu’il fournit, le présent projet propose des développements logiciels
intégrés au QOSoft. Ces ajouts logiciels au niveau du contrôle d’instrumentation et
de l’interface graphique permettent d’intégrer une caméra EMCCD à ultra-haute sensibilité
et ultra-faible bruit pour remplacer la caméra CCD refroidie existante ainsi qu’un
module d’illumination laser rotatif. Ce module d’illumination, développé par le groupe TomOptUS,
permet l’imagerie en mode transillumination ainsi que toutes les configurations
intermédiaires jusqu’à l’épi-illumination. Ce module permet en outre d’injecter une densité
de puissance lumineuse supérieure à celle possible avec la configuration actuelle du QOS. Le QOS et son logiciel mis à jour avec les ajouts faisant l’objet du présent projet sont
validés par des expériences de fluorescence et de bioluminescence sur fantômes et animaux
vivants.
13
Marek, Mary J. "PMOS CCD /." Online version of thesis, 1989. http://hdl.handle.net/1850/10563.
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Barutcu, Burcu. "The Design And Production Of Interference Edge Filters With Plasma Ion Assisted Deposition Technique For A Space Camera." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614574/index.pdf.
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Interference filters are multilayer thin film devices. They use interference effects between
the incident and reflected radiation waves at each layer interface to select wavelengths. The
production of interference filters depend on the precise deposition of thin material layers on
substrates which have suitable optical properties. In this thesis, the main target is to design
and produce two optical filters (short-pass filter and long-pass filter) for the CCDs that will
be used in the electronics of a space camera. By means of these filters, it is possible to take
image in different bands (RGB and NIR) by identical two CCDs. The filters will be fabricated
by plasma ion-assisted deposition technique.
15
Bouyer, Bernard. "Gravure sélective et sans dommage du silicium en mode triode synchronisé assistée d'un champ magnétique : application à la technologie C.C.D." Grenoble 1, 1990. http://www.theses.fr/1990GRE10074.
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Ce memoire decrit la mise en uvre d'un reacteur de gravure et de procedes associes, appliques aux dispositifs a transfert de charge (d. T. C. ) apres une analyse tres schematique des parametres de gravure, nous avons developpe un dispositif experimental utilisant deux electrodes excitees en radio-frequence et une bobine magnetique. Un systeme original de synchronisation des signaux appliques aux deux electrodes actives a permis de controler, d'une facon independante, la tension d'auto-polarisation sur l'electrode basse. Une cathode originale a champ magnetique dynamique compense a permis de densifier la decharge. Nous avons evalue les mecanismes et les performances de gravure du reacteur avec des gaz chlores et fluores. Dans le cas d'une forte topologie, l'anisotropie de gravure laisse des residus de silicium au pied des motifs appeles espaceur. Leur elimination a necessite la mise en uvre d'un troisieme gaz de gravure l'acide bromhydrique hbr qui, grace a ses proprietes, permet a la fois de graver les espaceurs et de proteger les flancs des motifs. L'utilisation judicieuse de ces trois gaz a permis de satisfaire au cahier des charges de la gravure des grilles c. C. D. Les defauts induits par la gravure plasma ont ete caracterises a partir des methodes d'analyse du silicium en volume (c-v, q#b#d). La nature des passivations ont ete determinees par des analyses de surface (xps, auger). L'utilisation du reacteur avec les ameliorations apportees: synchronisation des generateurs, champ magnetique dynamique et l'association d'une chimie appropriee ont permis de realiser des gravures de grille d. T. C. Avec d'excellentes performances et des taux de defauts reduits. Ces resultats devraient permettre d'ameliorer l'efficacite de transfert des circuits d. T. C.
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Lesser, Michael Patrick. "Charge-coupled device optimizations for astronomy." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184387.
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In the past decade, charge-coupled devices (CCDs) have rapidly become the astronomical imaging detector of choice for the visible and near-IR spectral regions. There are, however, several problems which have greatly reduced the availability of sufficient quality CCDs to the astronomical community. These include the low blue and ultraviolet quantum efficiency of thick devices, the lack of properly thinned devices, warped imaging surfaces, interference fringing, and the small size of the detectors themselves compared to telescope focal planes. This dissertation presents methods which can be used to optimize CCDs obtained from various manufacturers for astronomical observations. A new thinning technique which produces an optically flat surface across an entire CCD is demonstrated. A mounting technique which maintains a flat and stable imaging surface for thinned devices by bonding the CCD backside against a transparent glass support substrate is also demonstrated. Bump bonding of CCDs onto a silicon support before thinning is discussed as a future mounting/thinning technique. The design of antireflection coatings for the near-UV through near-IR spectral regions is explained and demonstrated on silicon diodes, allowing quantum efficiencies as high as 90% to be obtained. The reduction of interference fringing amplitudes by as much as 70% in the red and near-IR with AR coatings is also discussed. And finally, the design of CCD focal plane mosaics using the optimization techniques presented is discussed.
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Naghizadeh-Khouei, Jaber. "Application of CCDs (Charge Coupled Devices) to polarimetry and spectropolarimetry." Thesis, University of Glasgow, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266678.
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Nicoletti, Nathalie. "Contrôle dimensionnel par vision : Une application à des pièces découpées sur presses à grand débit." Besançon, 1988. http://www.theses.fr/1988BESA2036.
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Automatisation du controle de qualite par vision. Les pieces sont positionnees par un mecanisme a quatre barres. Les traitements d'image permettent d'obtenir des resolutions superieures aux precisions des cameras
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LeNoble, Maurice. "A GaAs cermet gate charge-coupled device." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29138.
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The design, implementation and evaluation of a 64-pixel, 4-phase GaAs cermet gate charge-coupled device ( CMCCD ) are described. It is demonstrated that the signal charge confinement and the signal charge capacity of the CMCCD are maximized when thin, highly doped active layers are used for implementing the device. The cermet/GaAs junction within an interelectrode gap of the CMCCD forms a barrier similar to a metal/GaAs Schottky barrier, as revealed by an investigation of the dc current-voltage characteristic of a cermet/GaAs Schottky barrier diode. A transmission line model is described for the cermet/GaAs junction within an interelectrode gap of the CMCCD and is used to demonstrate the relationship of the surface potential variation along the gap as a function of the clock frequency and the material parameters. It is shown that the surface potential variation is monotonic for all frequencies, which is desirable for minimizing the formation of energy troughs within the active layer. Energy troughs trap and release charge from passing charge packets, causing unwanted signal dispersion. A two-dimensional computer model is used to determine a theoretical maximum frequency of operation of the CMCCD. It is shown that a short transport electrode length for a fixed transport electrode pitch is preferable as it results in the maximum high frequency performance of the CMCCD for the lowest clock power. A computer simulation of a single electrode transfer of a charge packet is demonstrated using the two-dimensional computer model. The computer simulation indicates that efficient charge transfer takes place, suggesting that the CMCCD will have good performance. A GaAs CMCCD with an on-chip GaAs MESFET source follower amplifier has been produced using a six mask level fabrication procedure. The CMCCD and the output source follower amplifier are demonstrated to operate at 100 MHz. Charge transfer efficiencies of 1.00 and 0.998 for 100 MHz operation are obtained for the CMCCD using the impulse response method and the insertion loss method.<br>Applied Science, Faculty of<br>Electrical and Computer Engineering, Department of<br>Graduate
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Smith, David Ryan. "Radiation damage in charge coupled devices." Thesis, University of Leicester, 2003. http://hdl.handle.net/2381/30674.
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This thesis is concerned with the effects of radiation damage in CCDs used for space applications. The manufacturing process and operational principles of CCDs are presented in Chapter 2. The components of the space radiation environment, the two radiation damage mechanisms relevant to CCDs, and the effects of radiation on the operational characteristics of CCDs are described in Chapter 3. Chapter 4 presents a study to assess the suitability of novel L3Vision technology to applications in space. Two L3Vision CCDs were subjected to proton irradiations representative of doses expected to be received by spacecraft in low Earth orbit. Post-irradiation the devices were found to operate as expected, the effects of radiation on the operational characteristics of the devices being comparable to previous studies. The effect of low energy protons on CCDs is the subject of Chapter 5. The study was initiated in response to the finding that soft protons could be focused by the mirror modules of the XMM-Newton spacecraft onto the EPIC CCD detectors. Two EPIC devices were irradiated with protons of a few keV to find that soft protons cause more damage than that expected by the NIEL damage relationship, as they deposit most of their energy within the CCD. The observed change in CTI of the EPIC devices on XMM-Newton is however comparable to the pre-launch prediction, and the component attributable to low energy protons is small, < 20%. Chapter 6 presents a study of a specific radiation induced phenomenon, `Random Telegraph Signals'. Development of analysis software and the irradiation of two CCDs are discussed before a detailed characterisation of the generated RTS pixels is presented. The study shows that the mechanism behind RTS involves a bi-stable defect linked with the E-centre, in combination with the high field regions of a CCD pixel.
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Hill, Joanne E. "The charge coupled device as an X-Ray polarimeter." Thesis, University of Leicester, 1999. http://hdl.handle.net/2381/30620.
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New results of X-ray polarisation detection efficiencies are presented for two small pixel devices. EEV Ltd. have designed the first CCD X-ray polarimeter with an improved deep depletion layer of 80 urn, to maximise the device quantum efficiency at energies above 1 keV. A novel design concept has been utilised to minimise the pixel dimension whilst maximising production, the CCD has 4x9 um2 pixels. This device was tested and has been shown to be greater than a factor of two more efficient for polarisation measurements above 10 keV, than previously tested CCDs. The first successful measurements below 10 keV show a 5 - 10 % polarisation detection efficiency (modulation factor, M(E)), a significant result, due to X-ray optics having greater effective area below 10 keV. The smallest pixel CCD to date, with 2.4 um2 pixels, designed for optical purposes by Philips Ltd., is shown to have 26.2 % modulation at 10 keV. From the analysis of the data from these devices it has been recognised that charge diffusion, and thus the depletion depth, has a significant effect on the polarisation measurements. A model has been written to simulate polarised X-ray interactions in CCDs, and is shown to successfully model thinly depleted devices (Kodak KAF1400), in terms of polarisation detection efficiency. Further improvements have been identified to provide an accurate model for deeply depleted devices, in order to create a tool for optimising future CCD polarimeters. The modulation factors, M(E), for a 0.5 um2 pixel CCD have been estimated using the model, and it has been shown that a device of this type would provide a further factor of 2 improvement in M(E), with a significant measurement as low as 5 keV. The feasibility of a future mission including a CCD X-ray polarimeter has been investigated in detail, in terms of current and future technology. The XMM and the XEUS optics are considered in conjunction with both the EEV polarimeter and the modelled 0.5 urn2 pixel CCD. Two types of Astronomical sources are taken into account over a 5 - 20 keV energy range: bright galactic objects, e.g. The Crab Nebula faint extragalactic objects e.g. Active Galactic Nuclei (AGN). Using the XEUS optics, a 25 m focal length and an effective area maximised to 1 m2 at 1 keV yields observation times of less than 105 sees for a Crab measurement (polarisation 10 - 20 %, below 12.5 keV) and of the order 104 sees or less using a 0.5 urn2 pixel CCD. For measurements of the more faint AGN (polarisation 10 - 20 %) observation times are of the order 106 sees or below for the EEV CCD (7.5 - 10 keV) and the 0.5 um2 device (5 - 12.5 keV). Employing the XEUS optics for the measurement of the polarisation of AGN requires no further technological advancement if the EEV polarimeter is utilised, and the production of a 0.5 um2 pixel CCD is said to be within easy reach according to manufacturers.
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Amaden, Christopher Dean. "Fusion neutron damage to a charge coupled device camera." Thesis, Monterey, California. Naval Postgraduate School, 1997. http://hdl.handle.net/10945/8437.
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Approved for public release; distribution is unlimited<br>A charge coupled device (CCD) camera's performance has been degraded by damage produced by 14 MeV neutrons (n) from the Rotating Target Neutron Source. High energy neutrons produce atomic dislocation in doped silicon electronics. This thesis explores changes in Dark Current (J), Charge Transfer Inefficiency (CTI), and Contrast Transfer Function (CTF) as measures of neutron damage. The camera was irradiated to a fluence, Phi, of 6.60 x 10 (exp 12) n/ cm2. The camera temperature was lowered from room temperature to 267 K at a fluence of 4.7 x 10 (exp 11) n/cm2 to preclude saturation of the camera picture. With temperature compensations, J increased linearly with Phi. Four data points for J, CTF (ideal of 1.0), and CTI (ideal of 0.0) are given. Neutron irradiation significantly degraded the CCD camera performance; however, operating the camera at lower temperatures significantly reduces the effects. Damage thresholds for fluences greater than 6.60 x 10 (exp 12) n/cm2 and for all temperatures can be extrapolated from the results of this work
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Hayes, A. J. "A two phase charge coupled device on gallium arsenide." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354548.
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Beggs, Bruce Cameron. "Optical charge injection into a gallium arsenide acoustic charge transport device." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26681.
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There is a need for monolithic devices capable of spatial resolution in imaging and ionizing radiation detection. In this thesis, a GaAs acoustic charge transport device (ACT) was studied for this purpose. A new method of charge injection has been demonstrated for the ACT. Using near-infrared optical pulses incident through thin semi-transparent chromium windows, electron-hole-pairs were separated by the electric field in a depleted n-type channel region of the device. For light penetration less than the depth of the electron potential minimum, and for small injection levels, calculations indicated that electrons and holes were separated at their saturation velocities. Holes moving toward the surface of the substrate could recombine with electrons at an evaporated Schottky metal plate. Electrons moving toward the channel centre were bunched and transported by the electric field coupled to a <110> propagating surface acoustic wave (SAW) on (100) cut GaAs. Quantum efficiency, defined as the number of electrons collected at the output per incident photon on the GaAs surface, was greater than 9% at an optical wavelength of 730 nm. When compensation was made for the loss and
reflection due to the chromium windows, the quantum efficiency was in excess of 24%. Charge transfer efficiency was greater than 0.992 with the ACT clocked at 360 MHz. The demonstrated optical injection technique may be of use in future ACT imaging devices.<br>Applied Science, Faculty of<br>Electrical and Computer Engineering, Department of<br>Graduate
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Gedra, David R. "Design of a VLSI charge-coupled device analog delay line." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA296475.
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Giauque, Michael S. "Fusion neutron transient effects to charge coupled device camera images." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA367146.
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Thesis (M.S. in Applied Physics) Naval Postgraduate School, June 1999.<br>"June 1999". Thesis advisor(s): William B. Maier, II, D. Scott Davis. Includes bibliographical references (p. 43). Also available online.
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Pilon, Michael Joseph. "Inductively coupled plasma atomic emission spectroscopy using charge injection device detection." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185630.
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A unique echelle spectrometer system employing charge injection device (CID) array detectors for use in inductively coupled plasma atomic emission spectroscopy (ICP-AES) is described. The echelle spectrometer described offers numerous advantages over previous systems including improved light throughput and extended wavelength coverage including the vacuum-ultraviolet (VUV) down to 165 nm. Several improvements in CID array detector technology are also described. Low exposure level linearity is improved and full well capacity is increased by fabricating the CIDs with <100> silicon as opposed to <111> silicon. Low sensitivity in the far-ultraviolet (far-UV) has been considered a major disadvantage when using silicon based detectors due to absorbance in the overlying gate structure of the devices. The problem has been circumvented by utilizing a wavelength conversion phosphor to improve the effective sensitivity in the far-UV. The read noise of the CID has been reduced by a factor of 3 by utilizing a preamplifier on every row of the device. Utilization of this system for ICP-AES yields numerous advantages over conventional photomultiplier tube (PMT) based systems. Elemental detection limits comparable to or better than those obtained on PMT based instrumentation are achieved in the UV and visible regions. Sensitivities at wavelength less than 200 nm are degraded by a factor of 5 relative to PMT based systems due to decreased echelle grating efficiency in that wavelength region. In most cases, the advantages of continuous wavelength coverage provided by CID array detectors outweighs any loss in sensitivity. Operating parameters including precision, resolution and background correction are also discussed. Analysis of both the National Institute of Standards and Technology (NIST) Standard Reference Materials (SRM) 1643b and 1646 demonstrates that the system is capable of the simultaneous determination of a large number of elements at a large number of wavelengths with a high degree of accuracy even in spectrally complex matrices.
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EPPERSON, PATRICK MICHAEL. "APPLICATION AND CHARACTERIZATION OF CHARGE-COUPLED DEVICE ARRAY DETECTORS FOR ANALYTICAL SPECTROSCOPY." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184233.
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The research described in this dissertation is the first evaluation of two-dimensional charge coupled devices (CCDs) for low light level analytical spectroscopy. The electro-optical properties of several unique two-dimensional CCDs are evaluated, including quantum efficiency, detector read noise, linearity, dynamic range, dark current, and blooming. Theoretical models describing the sensitivity and dynamic range of CCDs on a single detector element basis are developed. Based on this model and the characteristics of a CCD detector system built for this research, it is shown that a single detector element of a CCD has comparable or superior sensitivity than the most sensitive single channel detectors. The results of the CCD detector system applied to fluorescence, emission, absorption, and time and spatially resolved spectroscopies are presented. The charge binning readout mode, which combines charge packets from several detector elements into a single charge packet, is critically evaluated for increasing the sensitivity and dynamic range of spectroscopic measurements. Equations describing the sensitivity and dynamic range enhancement achieved through charge binning are derived and experimentally verified in atomic emission and molecular fluorescence spectroscopies. The results of operating the CCD in two specialized readout modes developed in this research termed high-speed framing and spectral framing are presented. High speed framing allows the CCD to rapidly acquire two-dimensional images with high sensitivity. The spectral framing readout mode enables the CCD to record time-resolved spectra at a rate of approximately one spectra every two microseconds with great sensitivity. The design and evaluation of a CCD based molecular fluorescence spectrograph using a mercury pen lamp excitation source is described. The limit of detection for anthracene is 1 x 10 ⁻¹²M and is superior to the results obtained by fluorometers employing laser sources and photomultiplier detection. The design and evaluation of a spatially resolving spectrograph for absorbance spectroscopy of optically dense films is presented. The measurement of the absorption spectra of spatially heterogeneous metal-phthalocyanine thin-film electrodes with peak absorbances greater than five absorbance units is described.
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Toker, Emre 1960. "A prototype charge-coupled device based image acquisition system for digital mammography." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277308.
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A Charge-Coupled Device (CCD) based electronic imaging system is proposed to overcome limitations of conventional film/screen mammography systems at no additional risk or discomfort to the patient. This thesis presents the design, implementation and evaluation of a number of prototype systems incorporating the latest advances in x-ray intensifying phosphor screen, fiber optic reducer, and CCD technologies. System design is based on an x-ray intensifying screen optically coupled to a high resolution, cooled, scientific CCD through a fiber optic reducer. The performance of the prototype system is compared to theoretical predictions, to the ideal x-ray detector, and to conventional film/screen detectors. Images of breast phantoms captured by the prototype CCD-based system and by conventional mammography systems are presented. Experimental results indicate that the CCD-based system can provide "film quality" images within seconds of x-ray exposure in needle localization, fine-needle aspiration biopsy, and magnification procedures in mammography.
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Idroas, Mariani. "A charge coupled device based optical tomographic instrumentation system for particle sizing." Thesis, Sheffield Hallam University, 2004. http://shura.shu.ac.uk/19855/.
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This research investigates the use of charge coupled device (abbreviated as CCD) linear image sensors in an optical tomographic instrumentation system used for sizing particles. Four CCD linear image sensors are configured around an octagonal shaped flow pipe for a four projections system. The measurement system is explained and uses four CCD linear image sensors consisting of 2048 pixels with a pixel size of 14 micron by 14 micron. Hence, a high-resolution system is produced. Three main mathematical models based on the effects due to particles, light sources and diffraction are discussed. The models simulate the actual process in order to understand the limitations of the designed system. Detailed design of the optical tomography system is described, starting from the fabrication of the 'raybox 'of the lighting system, the design of the driving circuit in the detection system, the timing and synchronisation in the triggering system based on the PIC microcontroller and the data acquisition system. Image reconstruction for a four-projection optical tomography system is also discussed, where a simple optical model is used to relate attenuation due to variations in optical density, [R], within the measurement section. Expressed in matrix form this represents the forward problem in tomography [S][R]=[M] In practice, measurements [M] are used to estimate the optical density distribution by solving the inverse problem [R]=[S]-1[M]. Direct inversion of the sensitivity matrix, [S], is not possible and two approximations are considered and compared - the transpose and the pseudo inverse sensitivity matrices. The designed instrumentation system is calibrated using known test pieces and tested for accuracy, repeatability and consistency among measurements from different projections. The accuracy of the particle size measurement using the system is within 1 pixel i.e. + 14 micron (the maximum absolute error of 8.5 micron), with the maximum percentage error of 1.46%. Moreover, the system has a good repeatability and consistency - within 1.25 pixel. The range of particle size that has been tested using the system is between 0.18 mm up to 11 mm diameter. A spherical shaped and an irregular shaped particle are tested on the designed system to complete analysis of the overall performance of the system. This thesis is concluded with achievements of objectives of the research, followed with suggestions for future work.
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Hurle, Bernard Alfred. "The charge coupled device as a low light detector in beam foil spectroscopy." Thesis, University of Kent, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332296.
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Mendyke, Laura E. (Laura Edwards). "Computer control of a charge-coupled device in a prototype blood analysis machine." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/37751.
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McMenemy, K. R. "Photometric evaluation of aerodrome ground lighting." Thesis, Queen's University Belfast, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273182.
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Lee, Wing Kai. "The application of 2D and 3D particle image velocimetry (PIV) for measurement in high speed flows." Thesis, University of Warwick, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343141.
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Gilmor, Christopher Stephen Robertson. "In-line color monitoring of polymers during extrusion using a charge-coupled device spectrometer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/MQ58717.pdf.
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Gow, Jason Peter David. "Radiation damage analysis of the swept charge device for the C1XS instrument." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4311.
Full textAbstract:
This thesis is concerned with ensuring high energy resolution from the swept charge device (SCD) CCD54, essentially a non-pixellated version of the charge coupled device (CCD), for use in the Chandrayaan-1 X-ray Spectrometer (C1XS). Of particular interest is the effect on performance due to the radiation damage, caused by protons, the CCD54s used in C1XS will receive during the transfer to the Moon and during the two years in lunar orbit. Chapter 2 reviews the atomic structure, the formation and detection of X-rays, and the operation of a CCD. Chapter 3 discusses the space radiation environment and the damaging effects it has on CCDs, for example increasing dark current and charge transfer inefficiency. Chapter 4 presents the basic laboratory equipment and procedure used during the experimental work, and details the initial optimisation and characterisation, the pre-flight characterisation of devices available for use in C1XS, the measurement of the depletion depth, and quantum efficiency of the CCD54. Chapter 5 details the results of the initial proton irradiation study, intended to demonstrate the ability of the CCD54 to provide excellent scientific data over the two years at the Moon. Chapter 6 describes a second irradiation study covering a more detailed investigation of the damage effects, investigating dark current, trap energy levels, and charge transfer inefficiency. Chapter 7 describes work conducted to assist the C1XS science team in the development of an X-ray fluorescence model, to be used with X-ray spectra provided by the X-ray solar monitor and the spectra detected by C1XS, to provide elemental abundance information of the lunar surface. It also presents the initial C1XS results from the Moon, and a brief comparison of the CCD54 with other semiconductor X-ray fluorescence detectors. Chapter 8 describes the final conclusions and recommendations for further work, including a study of the radiation damage effects during the two years at the Moon and the future development of SCD detectors for use in space.
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Tan, Hiang Teik. "Modulation doped AlGaAs/InGaAs charge coupled device transversal filters for monolithic microwave integrated circuit applications." Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432647.
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Robinson, Simon. "Charge Coupled Device camera recording and computational analysis of flame propagation in a spark-ignition engine." Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/27203.
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Homogeneous charge combustion in a four stroke cycle spark-ignition engine was studied using through-piston-photography with a gated-intensified CCD camera. Analysis of computer stored multiple exposed flame front images was carried out for various engine conditions, in conjunction with the test data and cylinder pressure signals. Representative turbulence scales were inferred from the flame propagation and cylinder pressure data. Fractal analysis of flame edge contours resulted in a fractal dimension D3 in the range 2.12 to 2.23 corroborating data presented elsewhere. A correlation is presented here between the standard deviation of peak cylinder pressure and the fractal dimension D3.
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Liang, Yuanling. "Utilization of a scientifically operated charge-coupled device detector for high-performance thin-layer chromatographic analysis." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282688.
Full textAbstract:
A high-performance thin-layer chromatographic (HPTLC) separation system coupled with a scientifically operated charge-couple device detector (CCD) has been developed to improve the identification and quantitative analysis of pharmaceutical products and natural toxins. The combination of the fast, easy and high throughput properties of TLC, high speed, sensitivity, wide dynamic range of the CCD detector, and the high reproducibility and accuracy of the micro-nebulization sampler can be used to facilitate pharmaceutical industrial quality control and food industrial safety control. The application of this system in these areas has shown significant improvement in sensitivity, precision, and accuracy.
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Millichope, Allen John. "Application of a charge coupled device Raman microscope imaging system for quantitative analysis of aqueous surfactant phases." Thesis, Liverpool John Moores University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327678.
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Kim, Man-ho. "Three-dimensional numerical analysis of astronomical charge-coupled device image sensors for X-ray or UV detection." Thesis, University of Leicester, 1995. http://hdl.handle.net/2381/34791.
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Continuous advances in silicon processing technology have enabled devices to be more miniaturised and sophisticated. Most scientific Charge-Coupled Devices (CCDs), for example those used in astronomy, are following this trend; they are being scaled down and their doping profiles are becoming more complicated. Such trends increasingly require the use of three-dimensional (3-D) numerical simulations to provide improved designs. This thesis covers work focused on the three-dimensional simulation of buried-channel (BC) MOSFETs and CCDs. For BC MOSFETs a 1-D analytic model is developed to study their electrical characteristics and this is followed by 3-D numerical simulation work. Geometric-induced physical effects are thoroughly investigated using the 3-D simulation to optimise the scaling factor for the device. This simulation shows that 2-D simulation cannot estimate accurately the electrical characterisations of the narrow-channel and small geometry devices. For BC CCDs two X-ray astronomy CCDs are introduced: EPIC CCD as an open- electrode CCD imager and JET-X CCD. The optical properties of the EPIC CCD, used for ultra-low signal applications, were shown to be critically dependent on the dead layers and optical filter. It was clearly shown, for both devices, that 3-D simulations are useful for analysing charge storage and handling despite the complicated doping profile and sophisticated design structure. The charge handling capability of the JET-X CCD was found to be 9900 (electrons/?.m) using a 1-D analytical model. A 3-D static simulation of the JET-X CCD enabled estimations of the full-well capacity (60040 electrons), different depletion edge positions (< 5 % errors) and an optimised output gate voltage (between 3 and 4 V) for a higher charge transfer efficiency and demonstrated routes for optimisation and improvement. A 3-D transient simulation of the same device enabled estimations of the dynamic full- well capacity (61110 electrons), a dark current contribution (< 1 electron for a pixel clock cycle of 1.85 ?s) and a charge transfer inefficiency (< 0.001 % for a pixel clock cycle of 4.2 ns with a fall time of 0.4 ns). The 3-D simulation work suggests that a higher charge detection efficiency and charge transfer efficiency can be achieved with a higher-resistivity epi-material and a pixel clock cycle with a longer fall time (i.e. > 0.4 ns).
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Sartor, Mark Alan 1960. "Characterization and modeling of microchannel plate intensified charge coupled device signal to noise ratio variations with image size." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278136.
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It is a common misconception to consider the intensified charge coupled device (ICCD) to be simply a finite element detector. In reality, one must consider the ICCD as an optical system in and of itself, complete with its own throughput and point spread function. Only in this light can an accurate model for the ICCD performance be developed. Variations in signal to noise ratio (SNR) with image size can have broad implications in the design and modeling of ICCD based systems. Results from an experiment devised to measure the variation of SNR performance with input image size for selected Generation 2 microchannel plate (MCP) ICCD's are presented. Also presented is a generalized theoretical model for ICCD SNR performance for small images.
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Beukers, James. "Characterization of an E2V Charge-Coupled Device for the Michelson Interferometer for Global High-Resolution Thermospheric Imaging Instrument." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4448.
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This thesis presents the characterization process of an imaging device for a satellite. The camera system was built by the Space Dynamics Laboratory (SDL) and will be used in the Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument for National Aeronautics and Space Administration's (NASA) Ionospheric Con- nection Explorer (ICON) satellite. This mission will further scientists' understanding of the connection between the Earth's weather and ionospheric conditions. The ionosphere, a part of the atmosphere, interferes with satellite communications, causing disturbances and disruptions. By learning more about the ionosphere through the data collected by this instrument, scientists will better understand its effects on our communications.
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Carswell, Leo David Cecil. "The development and application of a charge-coupled device based instrument for at-site monitoring of algae and cyanobacteria in freshwaters." Thesis, University of Bedfordshire, 2002. http://hdl.handle.net/10547/324320.
Full textAbstract:
The research presented in this thesis describes the development and application of a portable, high-resolution instrument, specifically designed for the at-site monitoring of algae and cyanobacteria in freshwaters. The instrument incorporates a miniature charge-coupled device (CCD) based spectrometer and a low power combined deutelium and tungsten light source, enabling the absorbance to be measured between 200 - 850 nm at a resolution of 1.3 nm. A transmission dip probe with removable tips of 5, 10 and 40 mm pathlengths forms the sampling device. A specifically developed control program allows easy operation of the instrument. A linear response from 0.0 - 1.2 AU and a combined signal to noise ratio of 576: 1 for the instrument components resulting in a high baseline stability of 1.0 mAU drift over five hundred measurements being observed. The instrument provides in-vivo absorbance characteristics with high resolution across the visible spectrum. Up to twelve specific spectral features were commonly identified in the absorbance spectra of algae and cyanobacteria between 400 - 750 nm. Individual spectral features were linked to specific pigments, some of which were found to be taxonomically distinct. Fourth derivative analysis was proven to provide further enhancement of subtle spectral features. The instrument has a linear range for chlorophyll a up to 1000 !lg rl and a detection limit of 8 )lg rl using the 40 mm pathlength probe. Physiological adaptation to light and nutrient conditions were shown to have a significant effect on the in-vivo absorbance spectrum, therefore providing potential information on physiological status and health of a natural sample. Spectral analysis using principal component analysis (PCA) with classification based on the soft independent modelling of class analogy (SIMCA) method was used to classify nine species from three taxonomic classes, including four cyanobacteria (Microcystis aeruginosa, Anabaena variabilis, Aphanizornenon flos-aquae, Synechnococcus sp.), four chlorophyceae (Chlorella vulgaris, Scenedesmus acuminatus, Spirogyra mirabilis, Staurastrurn chaetoceros) and a single bacillariophyceae (Asterionella Formosa). Classification using the SIMCA method proved to be highly reliable and robust. Moreover, the addition of noise was found to have very little effect on the classification. Under laboratory conditions all nine species were correctly classified using 'unknown' spectra. At-site classification of natural samples and laboratory simulations have shown the robustness and reliability of the developed portable instrument. In combination with the data analysis techniques, the instrument is well suited to the proactive at-site assessment of algal and cyanobacterial blooms in eutrophic freshwater environments.
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Gurfinkel, Mikhail. "Cancer diagnostics using dynamic near-infrared optical imaging and fluorescent contrast agents." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3162.
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A new optical imaging modality has been developed for small animal in vivo imaging of near-infrared fluorescence resulting from fluorescent contrast agents specifically targeted to molecular markers of cancer. The imaging system is comprised of an intensified charge-coupled device (ICCD) for the detection of ultra-low levels of re-emitted fluorescence following the delivery of an expanded beam of excitation light. The design of the ICCD detection system allows for both continuous wave (CW) and frequency-domain modes of operation. Since the accurate acquisition of frequency-domain photon migration (FDPM) data is important for tomographic imaging, the imaging system was also validated using experimentally obtained FDPM measurements of homogenous turbid media and diffusion theory to obtain estimates of the optical properties characteristic of the media. The experiments demonstrated that the absorption and reduced scattering coefficients are determined least accurately when relative
rel
measurements of average light intensity IDC are employed either alone or in a
rel
combination with relative modulation amplitude data IAC and/or relative phase shift data
rel
. However, when FDPM measurements of are employed either alone or in
rel
combination with IAC data, the absorption and reduced scattering coefficients may be found accurate to within 15% and 11%, respectively, of the values obtained from standard single-pixel measurements; a result that suggests that FDPM data obtained from an ICCD detection system may in fact be useful in tomographic imaging. Furthermore, intensified-detection allows for sub-second exposure times, permitting the acquisition of dynamic fluorescence images immediately following administration of the contrast agent. Experimental results demonstrate that when coupled with a suitable pharmacokinetic model describing targeted dye distribution throughout the body, dynamic fluorescence imaging may be used to discriminate spontaneous canine adenocarcinoma from normal mammary tissue. A separate experiment demonstrates that pharmacokinetic analysis of dynamic fluorescence images enables one to estimate the rate constant governing Kaposi's sarcoma tumor uptake of an integrin-targeted dye and integrin receptor turnover rate. The rate constant for uptake was calculated to be 0.16-sec-1 while the turnover rate of the integrin receptor
was estimated to occur within 24-hours.
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Ramirez, Julian David Rodriguez. "Desempenho de dispositivos fotodetectores com multiplicação de elétrons por avalanche." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-29112016-134743/.
Full textAbstract:
Neste trabalho são apresentados os resultados obtidos no desenvolvimento de um sistema especificado para realizar testes na caracterização de dispositivos fotodetectores como fotodiodos de avalanche. O sistema de ensaios elaborado pretende auxiliar com na caracterização da fotodetecção em dispositivos de acoplamento de cargas com multiplicação de elétrons (EMCCD). O objetivo deste trabalho é avaliar o desempenho dos dispositivos fotodetectores para caracterizar os parâmetros mais significativos no processo da transdução óptica de modo a colaborar no projeto da eletrônica embarcada de controle e leitura da informação contida no EMCCD. A tecnologia da multiplicação dos elétrons em dispositivos CCD e diodos de avalanche têm aplicações importantes na vigilância de ambiente de luminosidade reduzida, astronomia, além de outras aplicações de imagens científicas incluindo as de baixo nível de bioluminescência para identificação de drogas e aplicações da engenharia genética. Para efeito de avaliação do desempenho do sistema fotodetector foi necessário desenvolver uma infra-estrutura para ter controle adequado da temperatura de operação do EMCCD. Foram nomeadas as opções com uma montagem de resfriamento com células Peltier e uma opção por criogenia resfriada com nitrogênio líquido. Os resultados obtidos são úteis na detecção de sinais luminosos ultrafracos minimizando o ruído do detector na aquisição de imagens com o auxilio da instrumentação de um filtro óptico sintonizável que será integrado no telescópio SOAR de 4 metros, instalado no Chile, para observações melhoradas com óptica adaptativa.<br>This work presents the results obtained in the development of a system specified to perform tests in the characterization of photo-detectors devices such as avalanche photodiodes. The test system is prepared to contribute to the characterization of the photo-detection in charge-coupled devices with electron multiplication (EMCCD). The objective of this study is to evaluate the performance of photo-detectors devices to characterize the most significant parameters in the optic transduction in order to collaborate in the project of an embedded electronic system for controlling and reading the information contained with the EMCCD. The technology of the electron multiplication in CCD devices and avalanche diodes has important applications in monitoring the environment of low light, astronomy and other scientific imaging applications including the low level of bioluminescence for the identification of drugs and applications of genetic engineering. For purposes of assessing the performance of the photo-detector it was necessary to develop an infrastructure to have proper control of the operating temperature of the EMCCD. Options were named with a montage of Peltier cell cooling and a choice of cryogenically cooled with liquid nitrogen. The results are useful in the detection of ultra weak light signals while minimizing detector noise during the acquisition of images from instrument comprising an optical tunable filter, that will be integrated into SOAR 4 meters telescope, installed in Chile, for observations improved with adaptive optics.
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Delaunay, Lionel. "Etude et réalisation d'un système de mesure du diamètre d'une fibre optique." Saint-Etienne, 1986. http://www.theses.fr/1986STET4004.
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Mesure du diamètre d'une fibre optique au cours de sa fabrication basée sur un principe physique interférométrique. Apres un calcul exact de l'intensité lumineuse diffusée par une fibre à saut d'indice éclairée perpendiculairement à son axe par un faisceau laser, on montre qu'il est possible d'interpréter le diagramme de rayonnement par l'interférence de deux rayons lumineux et on décrit deux méthodes de caractérisation du diamètre extérieur : l'une consiste à relier les déplacements des franges d'interférences aux variations du diamètre, l'autre consiste à compter le nombre de franges d'interférences dans un secteur angulaire donné au moyen d'une caméra à CCD et d'un microprocesseur
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Uhrich, Pierre. "Etude prospective d'un processeur optique en lumiere incoherente pour le traitement temps reel des donnees de radar a vision laterale." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13189.
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On presente une etude prospective pour un nouveau processeur optique effectuant le traitement des donnees de radar a vision laterale (sar) en temps reel. L'etage de correlation du calculateur optique, base sur un fonctionnement particulier des matrices ccd dit "add and shift" est valide experimentalement. On envisage egalement l'utilisation de ce processeur pour le traitement des signaux differents
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Meyer, Rüdiger Reinhard. "Quantitative Automated Object Wave Restoration in High-Resolution Electron Microscopy." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2002. http://nbn-resolving.de/urn:nbn:de:swb:14-1042118470265-98880.
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The main problem addressed by this dissertation is the accurate and automated determination of electron microscope imaging conditions. This enables the restoration of the object wave, which confers direct structural information about the specimen, from sets of differently aberrated images. An important member in the imaging chain is the image recording device, in many cases now a charge-coupled device (CCD) camera. Previous characterisations of these cameras often relied on the unjustified assumption that the Modulation Transfer Function (MTF) also correctly describes the spatial frequency dependent attenuation of the electron shot noise. A new theory is therefore presented that distinguishes between signal and noise transfer. This facilitates the evaluation of both properties using a detailed Monte-Carlo simulation model for the electron and photon scattering in the scintillator of the camera. Furthermore, methods for the accurate experimental determination of the signal and noise transfer functions are presented. In agreement with the Monte-Carlo simulations, experimental results for commercially available CCD cameras show that the signal transfer is significantly poorer than the noise transfer. The centrepiece of this dissertation is the development of new methods for determining the relative aberrations in a set of images and the absolute symmetric aberrations in the restored wave. Both are based on the analysis of the phase information in the Fourier domain and give each Fourier component a weight independent of its strength. This makes the method suitable even for largely crystalline samples with little amorphous contamination, where conventional methods, such as automated diffractogram fitting, usually fail. The method is then extended to also cover the antisymmetric aberrations, using combined beam tilt and focal series. The applicability of the new method is demonstrated with object wave restorations from tilt and focal series of complex inorganic block oxides and of carbon nanotubes filled with one-dimensional inorganic crystals. The latter specimens allowed for the first time a direct comparison between the phase shift in the restored object wave of a specimen with precisely known thickness and the value predicted by simulations.
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Ding, Hao. "Spectres optiques de diodes laser : methodes d'analyse des spectres, modelisation physique." Paris 11, 1988. http://www.theses.fr/1988PA112259.
Full textAbstract:
Etude de deux appareils de mesure de spectres optiques. Realisation d'un appareil a reseau grave et a dtc. Le cycle de mesure et la resolution obtenue sont 10 ms et 0,2 nm. Developpement d'un ensemble de programmes. Proposition de l'appareil a compensateur de babinet en vue de realiser des analyseurs compacts. - lasers a semiconducteurs : etude de leurs caracteristiques en relation avec les equations de continuite. Simulation des forces de langevin. Amelioration des equations classiques de continuite. Etude du fonctionnement continu, comportement transitoire, problemes de commution de gain, de chirping. Caracteristiques dynamiques en modulation d'intensite directe