Publications by authors named "Michael R Descour"

Non-linear microscopy has the potential to provide clinically useful information on the structure of biological tissue in vivo via an endomicroscope. The ability to use plastic as the optical material in a multiphoton objective was evaluated based on several criteria including autofluorescence, injection molding induced birefringence, and pulse broadening due to group velocity dispersion. An all-plastic, refractive ultra-slim endoscope objective was built with design specifications of NA=0.

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A hyperspectral Shack-Hartmann test bed has been developed to characterize the performance of miniature optics across a wide spectral range, a necessary first step in developing broadband achromatized all-polymer endomicroscopes. The Shack-Hartmann test bed was used to measure the chromatic focal shift (CFS) of a glass singlet lens and a glass achromatic lens, i.e.

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An estimated 1.6 million breast biopsies are performed in the US each year. In order to provide real-time, in-vivo imaging with sub-cellular resolution for optical biopsies, we have designed an ultra-slim objective to fit inside the 1-mm-diameter hypodermic needles currently used for breast biopsies to image tissue stained by the fluorescent probe proflavine.

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An integrated miniature multi-modal microscope (4M device) for microendoscopy was built and tested. Imaging performance is evaluated and imaging results are presented for both fluorescence and reflectance samples. Images of biological samples show successful imaging of both thin layers of fixed cells prepared on a slide as well as thick samples of excised fixed porcine epithelial tissue, thus demonstrating the potential for in vivo use.

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The purpose of this study was to determine whether in vivo images of oral mucosa obtained with a fiber optic confocal reflectance microscope could be used to differentiate normal and neoplastic tissues. We imaged 20 oral sites in eight patients undergoing surgery for squamous cell carcinoma. Normal and abnormal areas within the oral cavity were identified clinically, and real-time videos of each site were obtained in vivo using a fiber optic confocal reflectance microscope.

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A disposable high numerical aperture microendoscope objective has been designed, fabricated, and tested for use with a fiber confocal reflectance microscope. The objective uses high precision LIGA fabricated components to integrate imaging components and hydraulic suction lines into a housing that measures only 3.85 mm in outer diameter and 14.

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A core skill in diagnostic pathology is light microscopy. Remarkably little is known about human factors that affect the proficiency of pathologists as light microscopists. The cognitive skills of pathologists have received relatively little attention in comparison with the large literature on human performance studies in radiology.

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The design, analysis, assembly methods, and optical-bench test results for a miniature injection-molded plastic objective lens used in a fiber-optic confocal reflectance microscope are presented. The five-lens plastic objective was tested as a stand-alone optical system before its integration into a confocal microscope for in vivo imaging of cells and tissue. Changing the spacing and rotation of the individual optical elements can compensate for fabrication inaccuracies and improve performance.

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A novel solution to problematic ghost images is implemented by using tilted lens elements with polynomial surfaces. Tilting the lens surfaces sends reflections out of the imaging path. The nonrotationally symmetric polynomial surfaces correct aberrations caused by tilts.

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We propose a simple and powerful algorithm to extend the dynamic range of a Shack-Hartmann wave-front sensor. In a conventional Shack-Hartmann wave-front sensor the dynamic range is limited by the f-number of a lenslet, because the focal spot is required to remain in the area confined by the single lenslet. The sorting method proposed here eliminates such a limitation and extends the dynamic range by tagging each spot in a special sequence.

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This paper describes the design and fabrication of a novel array microscope for the first ultrarapid virtual slide processor (DMetrix DX-40 digital slide scanner). The array microscope optics consists of a stack of three 80-element 10 x 8-lenslet arrays, constituting a "lenslet array ensemble." The lenslet array ensemble is positioned over a glass slide.

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Infrared spectral features have proved useful in the identification of threat objects. Dual-band focal-plane arrays (FPAs) have been developed in which each pixel consists of superimposed midwave and long-wave photodetectors [Dyer and Tidrow, Conference on Infrared Detectors and Focal Plane Arrays (SPIE, Bellingham, Wash., 1999), pp.

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An endoscopic confocal microscope requires a high-performance, miniaturized microscope objective. We present the design of a miniature water-immersion microscope objective that is approximately 10 times smaller in length than a typical commercial objective. The miniature objective is 7 mm in outer diameter and 21 mm in length (from object to image).

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Direct photolithographic deforming of hybrid glass films is used to fabricate optical structures. The structure is fabricated in polyethylene-oxide-acrylate modified hybrid glass films with (1) binary and gray-scale photomasks using a mercury UV-lamp exposure and (2) maskless UV-laser patterning. Fabrication of isolated lenslets, lens arrays, and gratings is presented, including the associated exposure patterns.

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