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51.
A novel double‐layer alignment film (DLAF) was developed to obtain greater control of the alignment characteristics of the liquid crystal director. The DLAF consists of a thin fluorinated polymer layer on the top of a rubbed non‐fluorinated, non‐branched polyimide layer (PI 2555). Two types of fluorinated polymer with different chemical structures and wetting behaviour on PI 2555 were chosen, to provide either continuous or discontinuous top layers. The continuous top layer DLAF (DLAF‐1) exhibits an abrupt pretilt transition from planar to homeotropic as the top layer thickness increases. The discontinuous top layer DLAF (DLAF‐2) exhibits a gradual transition where the pretilt correlates with the coverage of fluorinated top layer. These two types of transitions fit with de Gennes' local Frederick's transition and Kwok's inhomogeneous alignment theories, respectively. The abrupt pretilt transition system may be promising for chemical/biosensor applications, whereas the gradual transition system is suitable for pretilt control in LCD devices. 相似文献
52.
This paper overviews some display technologies which play main roles on today's display market. And new technologies which may be used for tomorrow's display technologies have been discussed. New technologies will boost the development of display technologies. 相似文献
53.
Fast growing technology and requirements for testing of different types of materials and devices require new methods and systems
for investigation of their parameters. Among the quantities of high interest are shape, deformation, roughness, local materials
constants, displacement, and strain fields of elements under load. In the paper, we present novel solutions for digital holographic
cameras, which allow for remote monitoring and measurement of the above mentioned quantities at small mechanical objects or
at restricted areas of interest at big structures. The systems have compact design, “black box” measurement approach, and
allows for fast and accurate measurements performed directly at the element and often in outdoor environment. The principles
of digital and optoelectronic reconstruction and phase manipulation are described together with the exemplary measurement
results obtained by means of the cameras presented. 相似文献
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Temperature effect on dissipative holographicscreening-photovoltaic solitons in a biased dissipative system 下载免费PDF全文
In a biased dissipative photovoltaic-photorefractive system, this paper investigates the temperature effect on the evolution and the self-deflection of the dissipative holographic screening-photovoltaic (DHSP) solitons. The results reveal that, the evolution and the self-deflection of the bright and dark DHSP solitons are influenced by the system temperature. At a given temperature, for a stable DHSP soliton originally formed in the dissipative system, it attempts to evolve into another DHSP soliton when the temperature change is appropriately small, whereas it will become unstable or break down if the temperature departure is large enough. Moreover, the self-deflection degree of the solitary beam centre increases as temperature rises in some range, while it is decided by the system parameters and is slight under small-signal condition. The system temperature can be adjusted to change the formation and the self-deflection of the solitary beam in order to gain certain optical ends. In a word, the system temperature plays a role for the DHSP solitons in the dissipative system. 相似文献
58.
曝光系统离焦对平面全息光栅衍射波前的影响 总被引:1,自引:0,他引:1
波前像差是衍射光栅的重要技术指标,它直接影响光栅的分辨率。由光致刻蚀剂记录两束相干光干涉条纹是制作全息光栅的关键步骤。为了提高全息光栅曝光系统调整精度、减小离焦、降低光栅的衍射波前像差,从离焦对反射球面准直镜的准直光平行度的影响程度出发,分析了准直光平行度对全息光栅衍射波前像差的影响。理论分析和数值模拟结果表明,准直镜调整误差直接决定全息光栅衍射波前像差大小。以3种不同刻线密度光栅为例,得出了准直镜调整误差的允许变化范围。 相似文献
59.
基于PC机的虚拟现实技术研究 总被引:2,自引:0,他引:2
本文利用所需额外硬件很少的立体显示技术,研制了一种基于微机平台的虚拟现实系统。这个系统利用最新推出的微机版的三维图形标准Open GL建模,以实时动画形式实现了真正的交互性,立体视觉效果明显,可以给观赏者提供真实的临场感和亲自控制的参与感。与已研制出的“三维立体显示系统”相比,有了实质性的进步。 相似文献
60.
V.B. Markov 《Optics & Laser Technology》1996,28(4):319-325
Possible applications of holography for cultural heritage study, demonstration and restoration, particularly in practical museum applications, are discussed. In this respect two main applications of holography are of interest: display holography and technical holography. The latter includes holographic NDT methods, three-dimensional measurements of objects, memory systems, and so on. 相似文献