Fingerprints are the most accurate and widely used biometrics for human identification due to their uniqueness, rapid and easy means of acquisition. Contact based techniques of fingerprint acquisition like traditional ink and live scan methods are not user friendly, reduce capture area and cause deformation of fingerprint features. Also, improper skin conditions and worn friction ridges lead to poor quality fingerprints. A non-contact, high resolution, high speed scanning system has been developed to acquire a 3D scan of a finger using structured light illumination technique. The 3D scanner system consists of three cameras and a projector, with each camera producing a 3D scan of the finger. By merging the 3D scans obtained from the three cameras a nail to nail fingerprint scan is obtained. However, the scans from the cameras do not merge perfectly. The main objective of this thesis is to calibrate the system well such that 3D scans obtained from the three cameras merge or align automatically. This error in merging is reduced by compensating for radial distortion present in the projector of the scanner system. The error in merging after radial distortion correction is then measured using the projector coordinates of the scanner system.

Phase Measuring Profilometry (PMP) is the most robust scanning technique for static 3D data acquisition. To make this technique robust to the target objects which are in motion during the scan interval a novel algorithm called ‘Pattern Interleaving’ is used to get a high density single scan image and making Phase Measuring Profilometry insensitive to ‘z’ motion and prevent motion banding which is predominant in 3D reconstruction when the object is in motion during the scan time

Structured light pattern projection techniques are well known methods of accurately capturing 3-Dimensional information of the target surface. Traditional structured light methods require several different patterns to recover the depth, without ambiguity or albedo sensitivity, and are corrupted by object movement during the projection/capture process. This thesis work presents and discusses a color multiplexed structured light technique for recovering object shape from a single image thus being insensitive to object motion. This method uses single pattern whose RGB channels are each encoded with a unique subpattern. The pattern is projected on to the target and the reflected image is captured using high resolution color digital camera. The image is then separated into individual color channels and analyzed for 3-D depth reconstruction through use of phase decoding and unwrapping algorithms thereby establishing the viability of the color multiplexed single pattern technique. Compared to traditional methods (like PMP, Laser Scan etc) only one image/one-shot measurement is required to obtain the 3-D depth information of the object, requires less expensive hardware and normalizes albedo sensitivity and surface color reflectance variations. A cosine manifold and a flat surface are measured with sufficient accuracy demonstrating the feasibility of a real-time system.

The health and productive output of dairy cows can be closely correlated to individual cow feed intake. Being able to monitor feed intake on a daily basis is beneficial dairy farm management. Each cow can be addressed individually with minimal time required from those working with the animals. This is essential as time management is closely tied to resource management in a dairy operation. Anything that can save time and resources and increase profitability and herd health is a paramount advantage in dairy farming. This study examined the use of machine vision structured light illumination three-dimensional scanning of cow feed to determine the volume and weight of feed in a bin before and after feeding dairy cow. Calibration and control tests were conducted to determine the effectiveness and capability of implementing such a machine vision feed scanning system. Such a system is ideal as it does not obstruct workflow or cow feeding behavior. This is an improvement over existing systems as the system in this research study can be implemented into existing farm operations with minimal effort and costs.

Šiame darbe analizuojama šviesos įtaka regos procesui. Išnagrinėta mokslinė literatūra žmogaus regos, ryškumo, kontrasto ir spalvų suvokimo bei regos aštrumo klausimais. Išanalizuoti žmogaus regos proceso ypatumai, regos fiziologija. Pristatomi pagrindiniai fotometriniai dydžiai bei jų sąsaja su regos sistema. Atliktas tyrimas, kurio metu nustatoma regos aštrumo priklausomybė nuo paviršiaus apšvietos. Tyrime dalyvavo 50 žmonių. Tiriamieji suskirstyti į dvi: 40-50 ir 51-60 metų amžiaus grupes. Tyrime nustatyta, tiriamųjų regos aštrumo priklausomybė nuo įvairių apšvietų, apskaičiuoti vidutiniai tyrimo duomenų rezultatai, pateikta, tyrimo eigoje išryškėjusi adaptacijos tamsai įtaka. Šie tyrimo duomenys pavaizduoti grafiškai. Analizuojant teorinę medžiagą pastebėta, kad Lietuvoje, tai mažai tyrinėta sritis. Gauti tyrimo rezultatai rodo, kad padarius didesnius, daug daugiau tiriamųjų, kriterijų, apimančius tyrimus, būtų galima gauti įdomių rezultatų. / The subject of the work is the investigation of the visual acuity dependence on surface illumination. This final work analyzes the influence of light to visual process. Scientific literature was studied to look into the issues of human’s eyesight, brightness, contrast and color perception and visual acuity. The features of the human visual process and physiology of human’s eyesight have been examined as well. The work introduces the main photometric values and their relation to the visual system. The investigation has been carried out to determine the dependence of visual acuity on the surface illumination with 50 people participating in it. The people were divided into two groups according to their age: 40-50 and 51-50. The average data of the results have been estimated and various deviations from the mean shown up during the investigation are graphically presented in the work. While studying the theoretical material it was noticed that this field is still a byway in Lithuania. The findings suggest that if deeper and more criteria spanning researches were carried out, more revealing results could be expected.

Thesis (Ph. D.)--University of Washington, 1989. / Vita. Includes bibliographical references (leaves [494]-504).

Thesis (S.T.M.)--Yale University Divinity School, 1990. / Includes bibliographical references (leaves 78-83).

Univ., Diss.--München, 2001.

Thesis (Ph. D.)--Columbia University, 1993. / Department: Art History. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 205-210).

Thesis (Ph. D.)--University of Zurich, 1997. / Includes glossary. Includes bibliographical references (p. [925]-942) and index.