Problems of improving efficiency and quality of diamond-abrasive finishing of optical materials by tools with bounded polishing powders, including diamond powder, by means of the improvement of the machining technolog...
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ISBN:
(纸本)9780819482822
Problems of improving efficiency and quality of diamond-abrasive finishing of optical materials by tools with bounded polishing powders, including diamond powder, by means of the improvement of the machining technology and application of new tools with functionally oriented designs and characteristics of working layer are considered. A model has been proposed of the slime particle formation and directional removal as well as of the generation of a high-quality surface in diamond-abrasive finishing of optical materials taking into account the peculiarities of the mass transfer in the contact zone and statistic character of the distribution of slime particles by size. The dependences of the particle number on the diffusion angle and coordinate of the contact have been derived in the studies of the dynamics of collision and diffusion of slime particles. The coordinate dependence of the flat surface roughness of glass K8 optics in fine diamond grinding has been described. Interaction and dispersion of deterioration particles in a contact zone of the tool and a processed sample in the course of polishing is described and the dispersion structure of deterioration particles of the tool on slime particles and on deterioration particles is explained oscillatory. It is shown, that differential dispersion section of deterioration particles on slime particles no less than on deterioration particles as much as possible at corners of dispersion close to 0 and 180o on the central sites of a contact zone. Coordinate dependence of full dispersion section of deterioration particles of the tool and dependence of microprofile height of the processed surface on circular zones radius are calculated. Conformity of experimental and theoretical microroughness profiles of a polished surface on a quartz sample is shown.
Transparent conducting Fluorine-doped tin oxide (FTO) thin films were deposited on glass substrates by pulsed DC magnetron sputtering from cost saving metal targets. We observed lower resistivity and higher average tr...
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ISBN:
(纸本)9780819482822
Transparent conducting Fluorine-doped tin oxide (FTO) thin films were deposited on glass substrates by pulsed DC magnetron sputtering from cost saving metal targets. We observed lower resistivity and higher average transmittance in the visible range after the application of various post heating treatments. The electrical and optical properties of FTO films were investigated. When the annealing temperature is 400 degrees C in air, the average transmittance is 79.79% with the lowest resistivity of 1.38x10(-3) Omega-cm, carrier density of 2.27x10(20) cm(-3) and mobility of 20 cm(2)/V-s. When the annealing temperature is 400 degrees Cin a H-2 5%+N-2 95% atmosphere, the average transmittance is 79.75 % with the lowest resistivity of 1.26x10(-3) Omega-cm, carrier density of 2.17x10(20) cm(-3) and mobility of 22.8 cm(2)/V-s. When the annealing temperature is 350 degrees Cin vacuum, the average transmittance is 80.48% with the lowest resistivity of 1.23x10(-3) Omega-cm, carrier density of 4.40x10(20) cm(-3) and mobility of 11.6 cm(2)/V-s.
Non-mechanical variable lenses are important for creating compact imaging devices. Various methods employing dielectrically actuated lenses, membrane lenses, and/or liquid crystal lenses were previously proposed(1-4)....
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ISBN:
(纸本)9780819482822
Non-mechanical variable lenses are important for creating compact imaging devices. Various methods employing dielectrically actuated lenses, membrane lenses, and/or liquid crystal lenses were previously proposed(1-4). Here we present tunable-focus flat liquid crystal diffractive lenses (LCDL) employing binary Fresnel zone electrodes fabricated on Indium-Tin-Oxide using conventional micro-photolithography. The phase levels can be adjusted by varying the effective refractive index of a nematic liquid crystal sandwiched between the electrodes and a reference substrate. Using a proper voltage distribution across various electrodes the focal length can be changed. Electrodes are shunted such that the correct phase retardation step sequence is achieved. If the number of 2 pi zone boundaries is increased by a factor of m the focal length is changed from f to f/m based on the digitized Fresnel zone equation: f = r(m)(2)/2m lambda, where r(m) is m(th) zone radius, and lambda is the wavelength. The lenses operate at very low voltage levels (+/- 2.5V ac input), exhibit fast switching times (20-150 ms), can have large apertures (> 10 mm), and small form factor, and are robust and insensitive to vibrations, gravity, and capillary effects that limit membrane and dielectrically actuated lenses. Several tests were performed on the LCDL including diffraction efficiency measurement, switching dynamics, and hybrid imaging with a refractive lens. Negative focal lengths are achieved by adjusting the voltages across electrodes. Using these lenses in combination, magnification can be changed and zoom lenses can be formed. The promising results make LCDL a good candidate for non-mechanical auto-focus and zoom lenses.
The proceedings contain 22 papers. The topics discussed include: opticaldesign dependence on technology development;practical design considerations for modern photographic optics;display systems and registration meth...
ISBN:
(纸本)9780819477187
The proceedings contain 22 papers. The topics discussed include: opticaldesign dependence on technology development;practical design considerations for modern photographic optics;display systems and registration methods for mixed reality applications;efficient design process for the evaluation and control of flare in opto-mechanical systems;finding order in the design landscape of simple optical systems;design and optimization of a collimating optical system for high divergence LED light sources;point symmetric design approach to a wide-field wide-wavelength cat's eye retro-reflector anastigmat;fast catadioptric optics with large field of view;thinking outside the barrel: what really matters in modern photographic lensdesign;calculation of optical forces on a dielectric bead in a geometrically aberrated trap;and relationships between lens performance and different sensor sizes in professional photographic still SLR cameras.
作者:
Rockwell, Ken***
Post Office Box 8778 San Diego CA 92038-8778 United States
Because optical performance has increased so far with modern design software and aspherical manufacturing processes, optical performance is now the least important factor in modern photographic lensdesign. Far more i...
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Specific developments in optical technology over the past thirty years including refractive materials, thin film coatings and surface profiles will be discussed. A large variety of opticaldesigns which depend on some...
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作者:
Rockwell, Ken***
Post Office Box 8778 San Diego CA 92038-8778 United States
In the 1950s, cameras and lenses didn't communicate. optical bench tests were sufficient to characterize lens performance completely. Today, optics are only one small factor in the much larger electro-optical syst...
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A point symmetric design approach for creating a practical cat's eye retro-reflector (CERR) anastigmat lens with a wide field of regard (FOR), uniform reflectance and wide wavelength range is described. An anastig...
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optical detectors for illumination measurements have the known photopic response V(λ), which is implemented with the help of colored glass filters attached to silicon detectors. In the case of high precision photomet...
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