91 resultados para Cut thickness
Resumo:
A new 2-D quality-guided phase-unwrapping algorithm, based on the placement of the branch cuts, is presented. Its framework consists of branch cut placing guided by an original quality map and reliability ordering performed on a final quality map. To improve the noise immunity of the new algorithm, a new quality map, which is used as the original quality map to guide the placement of the branch cuts, is proposed. After a complete description of the algorithm and the quality map, several wrapped images are used to examine the effectiveness of the algorithm. Computer simulation and experimental results make it clear that the proposed algorithm works effectively even when a wrapped phase map contains error sources, such as phase discontinuities, noise, and undersampling. (c) 2005 Society of Photo-Optical Instrumentation Engineers.
Resumo:
Cr~(2+):ZnSe具有很宽的吸收带和发射带,是中红外波段优秀的可调谐激光材料。从吸收光谱、发射光谱以及角度调谐输出对Cr~(2+):ZnSe晶体的激光输出性能进行了研究。采用真空高温扩散法制备Cr~(2+):ZnSe晶体.获得了高浓度的Cr~(2+)离子掺杂的厚1.7 mm,直径10 mm的薄片ZnSe晶体。使用中心波长2.05μm,最大输出功率8 W的Tm离子掺杂的光纤激光器抽运,使用平凹腔结构搭建谐振腔,获得了最大平均功率1.034 W,中心波长2.367μm,线宽10 nm的连续激光输出。利用角度调谐的方法,对Cr:ZnSe晶体的调谐性能进行了研究,在100 nm范围内获得了调谐输出。
Resumo:
We report on a diode-pumped, cryogenic and room temperature operation of a Tm,Ho:YAlO3 (c-cut) laser. In a temperature of 77 K, an optical-optical conversion efficiency of 27% and a slope efficiency of 29% were achieved with the maximum continuous-wave (CW) output power of 5.0 W at 2.13 mu m. Acousto-optic switched operation was performed at pulse repetition frequency (PRF) from 1 kHz to 10 kHz, the highest pulse energy of 3.3 mJ in a pulse duration of 40 ns was obtained. In room temperature (RT), the maximum CW power of Tm,Ho:YAlO3 laser was 160 mW with a slope efficiency of 11% corresponding to the absorbed pump power. (C) 2008 Optical Society of America.
Resumo:
Color filters are key components in an optical engine projection display system. In this paper, a new admittance-matching method for designing and fabricating the high performance filters is described, in which the optimized layers are limited to the interfaces between the stack (each combination of quarter-wave-optical-thickness film layers is called a stack) and stack, or between stack and substrate, or between stack and incident medium. This method works well in designing filters containing multiple stacks such as UV-IR cut and broadband filters. The tolerance and angle sensitivity for the designed film stacks are analyzed. The thermal stability of the sample color filters was measured. A good result in optical performance and thermal stability was obtained through the new design approach. (c) 2006 Society of Photo-Optical Instrumentation Engineers.
Resumo:
The effects of repeating thickness periods on stress are studied in ZrO2/SiO2 multilayers deposited by electron-beam evaporation on BK7 glass and fused-silica substrates. The results show that the residual stress is compressive and decreases with an increase of the periods of repeating thickness in the ZrO2/SiO2 multilayers. At the same time, the residual stress in multilayers deposited on BK7 glass is less than that of samples deposited on fused silica. The variation of the microstructure examined by x-ray diffraction shows that microscopic deformation does not correspond to macroscopic stress, which may be due to variation of the interface stress. (c) 2005 Optical Society of America.
Resumo:
A series of ZnO thin films were deposited on ZnO buffer layers by DC reactive magnetron sputtering. The buffer layer thickness determination of microstructure and optical properties of ZnO films was investigated by X-ray diffraction (XRD), photoluminescence (PL), optical transmittance and absorption measurements. XRD results revealed that the stress of ZnO thin films varied with the buffer layer thickness. With the increase of buffer layer thickness, the band gap edge shifted toward longer wavelength. The near-band-edge (NBE) emission intensity of ZnO films deposited on ZnO buffer layer also varied with the increase of thickness due to the spatial confinement increasing the Coulomb interaction between electrons and holes. The PL measurement showed that the optimum thickness of the ZnO buffer layer was around 12 nm. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
Color filters are key components in an optical engine projection display system. In this paper, a new admittance-matching method for designing and fabricating the high performance filters is described, in which the optimized layers are limited to the interfaces between the stack (each combination of quarter-wave-optical-thickness film layers is called a stack) and stack, or between stack and substrate, or between stack and incident medium. This method works well in designing filters containing multiple stacks such as UV-IR cut and broadband filters. The tolerance and angle sensitivity for the designed film stacks are analyzed. The thermal stability of the sample color filters was measured. A good result in optical performance and thermal stability was obtained through the new design approach. (c) 2006 Society of Photo-Optical Instrumentation Engineers.
Resumo:
A series of silver films with different thickness were prepared under identical conditions by direct current magnetron sputtering. The optical properties of the silver films were measured using spectrophotometric techniques and the optical constants were calculated from reflection and transmission measurements made at near normal incidence. The results show that the optical properties and constants are affected by films' thickness. Below the critical thickness of 17 nm at which Ag film forms a continuous film, the optical properties and constants vary significantly as the thickness of films increases and then tends to a stable value which is reached at 41 nm. X-ray diffraction measurements were carried out to examine the structure and stress evolution of the Ag films as a function of films' thickness. It was found that the interplanar distance of (111) orientation decreases when the film thickness increases and tends to be close to that of bulk material. The compressive strains also decrease with increasing thickness. (C) 2007 Published by Elsevier B.V.