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ICALEO '97: Proceedings of the Laser Materials Processing Conference, 1997
The output of a laser is nearly monochromatic and is extremely coherent. Narrow linewidth or long coherence length is the primary operational characteristic of a laser and it allows the laser output beam to be focused to a tiny spot. The optical quality of a laser is a measure of the laser’s focusability.
William P. Latham, Aravinda Kar
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The output of a laser is nearly monochromatic and is extremely coherent. Narrow linewidth or long coherence length is the primary operational characteristic of a laser and it allows the laser output beam to be focused to a tiny spot. The optical quality of a laser is a measure of the laser’s focusability.
William P. Latham, Aravinda Kar
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Optical quality of the cat eye
Vision Research, 1971Abstract The modulation transfer function (MTF) of the cat's eye was measured. The MTF was determined by projecting square-wave-gratings of differing widths onto the retina, photographing the images of these gratings with a special fundus-camera, and making a photometric recording of the film.
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Optical quality of intraocular lenses
Journal of Cataract and Refractive Surgery, 1992The ANSI Z80.7 standard for intraocular lens quality is being updated. This paper identifies areas that require revision and suggests that a clear distinction between the lens design and the quality control test methods be made. The standard monofocal lens design consists of two spherical surfaces, and lens power can be specified by the thick lens ...
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Development of optical quality in the kitten eye
Vision Research, 1978Abstract The eyes of young kittens exhibit very poor optical quality which improves markedly as the animals mature. A longitudinal series of fundus photographs was made in eight eyes (four kittens) from which we derived the optical modulation transfer function at different ages.
R D Freeman
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The Diagnostic Quality of Optically Processed Radiographs
Radiology, 1976The diagnostic quality of optically processed radiographs was compared with that of unprocessed radiographs, using the number of lesions detected as a criterion. It was found that merely removing phase-shifted information with either a binary or focal spot filter alone did not improve image quality, however, use of the focal spot filter plus removal of
M, Trefler, E N, Milne
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Optical Image Quality in the Peripheral Retina
American journal of optometry and physiological optic, 1978ABSTRACT A double‐pass, photoelectric, ophthalmoscopic method was used for objective study of the variation in image quality across the retina in terms of the reflected image of a fine line, the line‐spread function. Radial and tangential line‐spread functions have been studied with active and paralyzed accommodation at eccentricities
J A, Jennings, W N, Charman
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The optical quality of the human eye revisited
Ophthalmic and Physiological Optics, 1997A subjective assessment of the optical quality of the human eye may be derived from a comparison between the contrast sensitivities obtained in response to a refracted grating display and a non-refracted grating display. The former may be generated on a cathode ray tube (CRT) while the latter may be obtained with laser interference fringes observed in ...
R M, Webb, A, Sahal, J D, Morrison
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Physics Bulletin, 1985
Since the time of Galileo, many tasks performed in optical polishing workshops have remained essentially unaltered. Grinding and polishing optical components to their final shape is still a laborious task.
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Since the time of Galileo, many tasks performed in optical polishing workshops have remained essentially unaltered. Grinding and polishing optical components to their final shape is still a laborious task.
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Image-quality assessment in optical tomography
2004 2nd IEEE International Symposium on Biomedical Imaging: Macro to Nano (IEEE Cat No. 04EX821), 2005Modern medical imaging systems often rely on complicated hardware and sophisticated algorithms to produce useful digital images. It is essential that the imaging hardware and any reconstruction algorithms used are optimized, enabling radiologists to make the best decisions and quantify a patient's health status.
Matthew A. Kupinski, Eric Clarkson
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The Tear Film and the optical Quality of the Eye
The Ocular Surface, 2010The stability of the tear film plays an important role in the optical quality of the eye. Various methods have been developed to quantify the contribution of the tear film to optical quality, including the double-pass optical method, Hartmann-Shack wavefront sensing, videokeratoscopy, retroillumination analysis, and interferometry.
Robert, Montés-Micó +4 more
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