Cressida M. Harding

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A previously presented method for modeling Kolmogorov phase fluctuations over a finite aperture is both formalized and improved on. The method relies on forming an initial low-resolution Kolmogorov phase screen from direct factorization of a covariance. The resolution of the screen is then increased by a randomized interpolation to produce a Kolmogorov(More)
The paper describes a volumetric approach to depth estimation for robot navigation with use of only an approximately calibrated translating camera. Our approach is related to techniques for photo-realistic object reconstruction but with the emphasis on issues associated with navigation. The technique performs three-dimensional matching by a process of image(More)
The spontaneous-emission factor in an unstable-resonator semiconductor laser is enhanced by more than 2 orders of magnitude compared with that of a Fabry-Perot semiconductor laser having the same volume. A clear linkage has been observed among the spontaneous-emission factor, the waveguiding property, and the width of the lasing spectral envelope.
Visible light (665 nm) laser diodes employing a strained-layer, single quantum well, graded index separate confinement heterostructure were fabricated from epitaxial wafers grown by metalorganic chemical vapor deposition. Threshold current densities for single element, uncoated, broad-area diodes operated cw as low as 425 A/cm’, cw power outputs of 340 mW(More)
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