Vision correction by intraocular lenses

The advantages of correcting the refractive errors of the eye (nearsightedness and farsightedness) by introocular phakic (i.e., without removing the crystalline lens) lenses over the other types of correction are considered. A relation between the optical power of spectacle glasses and contact and phakic lenses is obtained and analyzed. New, more accurate approximate formulas for calculating the optical power of intraocular artificial lenses and phakic lenses are derived. It is shown that the deviation of calculations by the proposed formulas from the calculations by the formulas based on geometrical optics are much less than the deviation of calculations by the regressive formulas used in ophthalmic practice.     

节能玻璃的光谱测试

为从光谱方面分析典型建筑用节能玻璃的特性,以现时建筑施工中常用的几种节能玻璃为研究对象,采用WGD-8A型组合式多功能光栅光谱仪对样品进行200～800nm的光谱测试。通过光谱测试发现:未经镀膜处理的普通钢化玻璃光透过率比较高,但是对波长没有选择性,无光谱节能效果;镀膜(贴膜)玻璃可见光透过率各异,普遍具有滤红外的节能效果;中空玻璃可见光透过率降低,有明显阻挡红外光的效果。部分镀膜(贴膜)玻璃具有可见光谱颜色选择性。这一测试成果,可作为建筑设计中选择玻璃的参考。     

CAD在光学机械设计(OMD)中的应用实例

本文通过CAD技术在光学机械设计(OMD)中的二个应用实例,具体说明了CAD技术在OMD中的应用方法,并用各种图,概括地展现了CAD技术用于OMD中的优越性及前景。     

CAD在跟瞄仪器设计中的应用

本文通过CAD技术在跟瞄仪器设计中的应用实例,具体说明了计算机辅助设计在跟瞄仪器设计、分析中的应用方法,概括地展现了CAD技术应用在该领域中的优越性及前景。     

渐变焦式眼镜综述

叙述了渐变焦式眼镜的发展概况，分析了渐变焦式眼镜附加象差的性质和产生的原因，探讨了渐变焦式眼镜的发展前景。     

Deformation analysis of micro/nano indentation and diamond grinding on optical glasses

The previous research of precision grinding optical glasses with electrolytic in process dressing (ELID) technology mainly concentrated on the action of ELID and machining parameters when grinding,whic...     

Nanoinhomogeneities in glasses and their role in optical memory phenomena and charge transfer processes

To explain the basic features of the response of disordered materials (glasses) to irradiation by light, a new approach based on the assumption that glasses have the so-called “medium-range” order (inhomogeneities with the characteristic scale of ∼1 nm) is proposed and justified. The structure of inhomogeneities depends on the bond type: glasses with covalent directed bonds (strong glasses) at nanometer scales are similar to their crystalline ancestors. Glasses with non-directed bonds (ion and van der Waals bonds) do not form crystalline nanoinhomogeneities, though the existence of a certain medium-range order is typical for them. Using the concept of an inhomogeneous structure of glasses at nanometer scales, it is possible to explain the physical properties demonstrated by these materials: structural factor, specific features of the density of vibrational states in the terahertz range, mean free paths at frequencies below the boson peak frequency, optical memory phenomenon, and specific features of charge transfer. The proposed approach is an alternative for the widely used approach that involves construction of specific defects understood as violations of coordination of individual atoms, as quasi-molecular complexes, or as two-level states with no particular information about them. This approach reflects the specific features of the vitreous state, is universal, and is not based on a particular chemical nature of the material.     

一种分析视频眼镜图像清晰度的新方法

依据光学传递函数与级联光学传递函数理论,通过CCD相机拍摄视频眼镜显示的ISO12233分辨率测试图像卡,运用Imatest软件分析视频眼镜中光学成像系统的质量和图像分辨率(SFR)参数。对Google Glass,Epson BT-200,Optinvent ORA-1,奥图科技Cool Glass One以及Raypai的几种视频眼镜进行了测试与分析,获得每一种视频眼镜的图像分辨率调制传递函数(MTF)结果并进行比较。MTF结果与实际视觉观测结果基本相符,表明这种测试方法与Imatest软件分析计算的正确性。     

Effect of Flash Temperature on Tribological Properties of Bulk Metallic Glasses

The tribological properties of Cu-based and Zr-based bulk metallic glasses (BMGs) sliding against Si₃N₄ under dry and water lubrication were studied on a pin-on-disc tribometer. The wear mechanisms of bulk metallic glasses were investigated based on the calculated flash temperature. The friction coefficients if fully amorphous alloy are about 0.7, while those of BMGs with nanocrytalline are a little higher. The wear rates of Cu-based BMG (V101) are about one order of magnitude lower than those of Zr-based BMG (Vit1) under dry friction, even two orders of magnitude lower under water lubrication. The wear resistance of bulk metallic glasses was influenced by the flash temperature. The calculated flash temperature (3,337 K) on the friction surface of Zr-based amorphous alloy exceeds its glass transition temperature, even its melting temperature. The high flash temperature leads to glass transition accompanied with viscous flow and material transfer, which is responsible for the poor wear resistance of Zr-based BMGs.     

Dynamic analysis of a PDP exhaust hole processing equipment considering glass substrate interaction

Exhaust hole drilling is one of the PDP (Plasma Display Panel) manufacturing processes to make about 1mm diameter holes for sucking out air in order to generate vacuum between two PDP glass substrates. In the drilling process, bigsized glasses about the size of a queen size bed are loaded, aligned, drilled, and unloaded, during which the dynamic interactions between glass and the handling equipment are very significant. To analyze exhaust hole drilling equipment dynamics, interaction with glass substrates that have somewhat different material properties from general glasses should be considered. The Young’s modulus and Poisson ratios of the substrates have been determined experimentally and verified via computation that simulates a well-known three-point bending test. Dynamic interaction of the glass with the handling equipment is modeled using a flexible glass and rigid body handling equipment models. The velocity profile by which the glasses are driven and the material properties of the handling equipment components contacting with the glasses are evaluated in view of the structural integrity of the glass and the operational efficiency of the equipment. The dynamic model is demonstrated to be an effective design tool for an exhaust hole drilling machine. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Tae Oh Tak received his B.S. and M.S degree in Mechanical Design and Production Engineering from the Seoul National University in Korea in 1982 and 1984, respectively. He obtained his Ph.D. degree from the University of Iowa, USA in 1990. He is currently a professor at the Department of Mechanical and Biomedical Engineering at the Kangwon National University in Chuncheon, Korea. His research interests are multibody dynamics and sensitivity analysis.     

SIMS analyses of rare earth elements in natural minerals and glasses: An investigation of structural matrix effects on ion yields

An investigation of the influence of matrix structure upon secondary ion signals for rare earth elements (REEs) in various silicates (amphiboles, clinopyroxenes, garnets, and plagioclases) was carried out by means of conventional energy filtering technique (CEF). Such matrices were analysed both as natural crystals and fused glasses. Of the selected REEs for the different minerals, only La showed an intensity relatively higher than Si in glassy amphiboles and augites. The hypothesis proposed of an ionization behaviour of La that differs with respect to other REEs in silicates has not been confirmed in plagioclases. All other relative REE ion yields from crystals and glasses agreed within the statistics of measurement for all investigated matrices. Moreover, any difference between crystal and glass REE ionization appeared not to be attributable to varying charging conditions during analysis under O^? primary beam bombardment. Laboratory contamination during glass preparation and/or the presence of residual light REE-enriched micron-scale accessory phases (e.g., apatite) could be responsible for the higher La/Si signal in augite and amphibole glasses. Results obtained show that the efficiency of REE ionization compared with that of Si. generally is not affected by the sample structure as far as high energy secondary ions are concerned; therefore, glasses obtained by fusing silicate minerals are suitable for analytical work and can be employed to calibrate REE ion signals for quantitative purposes.     

国外新型环境监测光学技术的发展趋势

本文简要介绍了目前国外在环境监测方面所采用的新技术及开发的新型仪器探讨了此类仪器在环境监测及石化企业中的推广前景。     

新型按摩眼镜设计

介绍一款新型按摩眼镜,此眼镜可收集人体体温传递的热能和脉搏振动的动能,来产生磁场强度较低的脉动磁场,以达到长期佩戴而不影响日常生活和学习的目的,且能使眼部毛细血管内部产生微电流,以脉冲形式辅助血液经络循环,达到通经活络,调和气血,促进血液循环,进而改善眼部疲劳,起到预防和校正视力的效果.     

Transparent single-point turning of optical glass:: A phenomenological presentation

Single-point turning of optical glasses by continuous chip generation at elevated temperature is described in this paper: appropriate temperatures are ranged around the American softening point. Optimisation of tool-setting, depth of cut, local heat supply and other parameters resulted in transparent turning of a number of optical glasses by a process combining abrasive turning by single-point machining and viscous relaxation of the glass surface immediately after removal of the continuous chip     

Modelling the erosion rate in micro abrasive air jet machining of glasses

Micro abrasive jet machining (MAJM) is an economical and efficient technology for micro-machining of brittle material like glasses. The erosion of brittle materials by solid micro-particles is a complex process in which material is removed from the target surface by brittle fractures. The rate of material removal is one of the most important quantities for a machining process. Predictive mathematical models for the erosion rates in micro-hole drilling and micro-channel cutting on glasses with an abrasive air jet are developed. A dimensional analysis technique is used to formulate the models as functions of the particle impact parameters, target material properties and the major process parameters that are known to affect the erosion process of brittle materials. The predictive capability of the models is assessed and verified by an experimental investigation covering a range of the common process parameters such as air pressure, abrasive mass flow rate, stand-off distance and machining time (for hole machining) or traverse speed (for channel machining). It shows that model predictions are in good agreement with the experimental results.     

特种火石玻璃单坩埚漏料工艺研究

本文根据流体力学原理及模拟实验结果,设计出实用的铂坩埚及搅拌器.建立了一套熔制特种火石光学玻璃的实验装置,确定了特种火石光学玻璃单坩埚漏料新工艺.     

渐进多焦点镜片的设计与慢刀伺服车削

为解决自由曲面眼镜片设计加工的难题,进行了渐进多焦点镜片的设计和加工。提出了渐进多焦点曲面的参数化设计方法,通过控制曲面曲率来控制曲面的面型,避免了复杂的数学计算。在对曲面光焦度和像散分布进行计算的基础上对曲面进行评价。提出了离散曲面的刀触点生成方法,将慢刀伺服车削技术用于该渐进多焦点曲面的加工。实验结果证明了设计方法的正确性和加工方法的可行性。     

Properties and structures of Co-based metallic glasses

A fundamental study on Co-based metallic glasses has been conducted. The study focused on understanding the changes of the properties and structures of an Fe-B-Si glass as a function of Co, Co-Ni, Co-Mn, and Co-Ni-Mo additions. The separate addition of Co, Co-Ni, Co-Mn, and Co-Ni-Mo elements was successful in such a way that four new metallic glasses were produced. The compositions of the new glasses are Fe₆₆Co₁₈B₁₅Si₁, Co₆₆Fe₄B₁₄Si₁₅, Co₇₆Fe₂Mn₄B₁₂Si₆, and Co₆₉Fe₄Mo₂B₁₂Si₁₂. Consequently, an evaluation of the physical and magnetic properties was determined. Furthermore, the internal and surface structures of the glasses have been characterized by a transmission electron microscope (TEM), and a scanning tunneling microscope (STM), respectively. A comparison between the internal and surface structures of the glasses was carried out on both amorphous and crystalline forms. As a result, a correlation between the properties and structures of the glasses is established.     

电致变色膜改善穿透式视频眼镜对比度的方法

穿透式视频眼镜在日常使用中普遍存在对比度不高,成像效果不理想的缺点。依据电致变色膜加电状态下能够削减环境光的原理,对穿透式视频眼镜的对比度进行改善。通过TracePro软件光学仿真及成像亮度计进行实验验证,对EPSON BT-200穿透式视频眼镜进行测试和分析,验证该方法的可行性。实验数据与实际视觉观测结果基本相符,表明了这种方法的正确有效。     

Improvements on a laser scattering technique for droplet size measurements applied to a gas-liquid separation equipment

The knowledge of droplet size distributions in a gas-liquid separation equipment is of high relevance due to the importance of removal efficiency in these systems. Different techniques could be used to measure droplet size, being one of them the diffraction of a laser beam. The laser is located behind glasses, being the formation of droplets on the glasses one of the main problems encountered when using this technique.Due to this major problem, different innovative solutions have been proposed and implemented to the gas-liquid separation column in order to obtain satisfactory results. A shutter mechanism, a purge gas and combination of these two solutions were tested. It was shown that the modified technique is suitable for liquid droplet measurements under ambient conditions.It has been also shown that the combination of these two solutions reduced considerably the amount of droplets that interacts with the glasses, allowing getting better data.