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1.
讨论了用单色激光器记录三个彩虹全息图来合成二维真彩色全息图时,彩色全息图的彩色特性、狭缝位置和色彩亮度等问题.  相似文献   

2.
刘艺 《光电工程》1996,23(6):60-65
通过分析全息图记录的干涉条纹图样,指出对于二维全息图,一束再现光将产生两个对称于全息图面的物象,两束对称于全息图面的再现光将产生位形相同的物象;三维全息图的再现,象的对称性不变,但原物象的对称再现象有一定的弥散,对称光再现时,等亮度再现象出现在全息图转动一个角度之后,实验上制作了具有清晰透射彩虹全息象的象面反射全息图。  相似文献   

3.
《国际防伪》2006,(3):74-77
激光全息图像防伪产品,因其可目视直观识别,在市场上广为推崇,随着相关技术的发展,全息制品的开发也日新月异,一方面,激光全息制版技术不断革新,如计算机全息图、双光束雕刻全息图、真彩色全息图、合成全息图、密码全息图等都可以应用于透明全息技术,  相似文献   

4.
在分析递归二元搜索算法合成计算全息图原理的基础上,计算机编程设计了递归二元搜索型计算全息图,并在实验上研究了计算全息图的恢复象。实验结果表明,递归二元搜索算法可合成任意波前分布的傅里叶变换计算全息图,并具有恢复象质量好,衍射效率高的特点。  相似文献   

5.
在消声器进出口管道平面波截止频率以上,高阶模态被激发,传统方法假设进出口为平面波计算消声器传递损失的方法已不再适用。基于有限元法,把进出口面划分出若干个单元,将每个单元上的声场分布近似为平面波,建立基于单元能量叠加计算消声器传递损失的方法,并使用本文方法和Virtual.Lab Acoustics软件计算了三种类型消声器的传递损失,分析了非平面波现象。结果表明,本文方法可行且能够有效地考虑非平面波的影响。  相似文献   

6.
《现代材料动态》2011,(3):17-17
该方法主要包括以下几个步骤:首先,科学家将X射线激光束分成两个单独的光束。之后利用多面镜,强行使其中一束发生轻微弯曲,使得两激光束到达研究对象时相差0.00000000000005s(50飞秒)。这样,两激光束就共同产生了一个研究对象的“双全息图”,该全息图编码了研究对象在两个时间点的结构  相似文献   

7.
激光全息信息具有大容量、多信道、色彩丰富、给人以强烈的视觉冲击效果,随着模压全息技术的发明,全息技术在包装防伪印刷中得到广泛的运用:彩虹全息图是最常用的模压全息图,拍摄方法很多.本文采用一步彩虹法,设计出一步彩虹全息的拍摄光路,分析实验参数,成功拍出全息图,并进一步总结拍摄高质量一步彩虹全息图的经验。这些参数和经验对其他拍摄方法具有借鉴作用。  相似文献   

8.
自从极品云烟率先在其包装上烫印三维立体全息图以来,模压全息图作为防伪和促销的手段,已逐渐广泛应用于各类高档香烟的软硬包装中。巧妙地利用全息图,以其普通印刷所不可代替的图象显示方式来提高传统印刷技术的表现能力,已成为当今高档印刷包装的发展趋势。  相似文献   

9.
自从1979年世界第一张商业用模压全息图产生,由于其具有科技含量高、批量生产、精美、防伪、制作成本低且方便等特点,广泛应用于防伪包装领域。目前国内市面上常见的防伪标识,主要是模压彩虹全息图。这种全息图有立体感,图像清晰,色彩绚丽,保密级数高,具有神秘感和强烈的时代感。  相似文献   

10.
提出了用递归直接二元搜索算法(DBS)设计二元位相计算全息图的新方法,分析了DBS型位相计算全息图的设计原理,计算机模拟定量地分析恢复象的质量和衍射效率,分析结果表明该位相计算全息图恢复象质量较好、衍射效率高,在光电技术、光学信息处理等领域中有重要的应用前景  相似文献   

11.
A new hybrid optical device that is capable of splitting a monochromatic laser beam into an arbitrary number of lines over a wide angle is presented. It consists of a binary surface-relief computer-generated phase hologram and a continuous parabolic surface-relief grating. In this device the phase hologram serves to generate three small, parallel lines while the continuous parabolic surface-relief phase grating acts as an array of diverging parabolic lenses to widen these lines. The binary surface-relief was generated into one side of a quartz substrate through a plasma-etching process, and the parabolic profile was generated into a thick photoresist deposited on the other side of the quartz substrate. Calculations showed that a diverging parabolic lens with a f-number of 0.5 would deliver the desired optical pattern of multiple beams distributed over 90 degrees . A surface-relief depth of 6.0 mum was calculated with consideration of the phase distributions of such lens. The parabolic profiles were fabricated in a 10-mum-thick photoresist, by use of a contact exposure through a mask with a space pattern of repetitive 4- and 6-mum lines. He-Ne laser light was passed through a device that generated three parallel lines over a 90 degrees angle. The resulting diffraction patterns were characterized, and a satisfying result was obtained. The resulting multiple-line pattern can be used in robot vision and other applications.  相似文献   

12.
13.
Jiang C  Fan C  Guo L 《Applied optics》1994,33(11):2111-2114
Based on conventional one-step true-color rainbow holography, a new true-color rainbow holography of a three-dimensional diffused object is presented. By means of conjugate reconstruction with a onewavelength laser of a master hologram recorded with three laser wavelengths, the hologram can be transferred to a single type of recording material with a single exposure to achieve true-color holographic display. Therefore a photoresist master can be produced for embossing copy.  相似文献   

14.
Zhu P  Liu X  Xu Z 《Applied optics》1995,34(5):842-845
A display hologram of an object can be recorded and reconstructed in three primary colors if the angular selectivity of volume recording media is exploited. Three holograms are recorded in the same medium, each at a different primary color. These three holograms are reconstructed by simultaneous illumination of the hologram with the original reference beams. By proper choice of the angles that the reference beams make to the hologram, it is possible to suppress strongly cross talk between the different reconstructions (e.g., the red object reconstruction in green light). The technique exhibits high resolution, high diffraction efficiency, and vivid colors. Through the addition of three holographically recorded volume gratings it is possible to reconstruct the hologram with a beam of white light. The saturation and brightness of each primary color in the reconstruction can be adjusted by selection of an appropriate thickness for the corresponding grating.  相似文献   

15.
Zhou HJ  Morozov V  Neff J  Fedor A 《Applied optics》1997,36(17):3835-3853
The design of a bidirectional free-space optical interconnect system is presented. Vertical-cavity surface-emitting laser (VCSEL) arrays as a coherent light source and VCSEL beam collimation are described. Hologram array design and a way to improve the diffraction efficiency by use of a copying technique utilizing Dupont photopolymers are presented. Scattering from the hologram as a noise source is measured. An optical model for the design of system parameters such as the VCSEL beam diameter, size and apodization of the hologram, and size of the detector is given on the basis of cross-talk analysis of the system. The effect of VCSEL wavelength variation on system design is considered. Aberrations caused by the Fourier lens in the system are calculated, and ways for correction of the aberrations are discussed.  相似文献   

16.
Interferometric recording is applied to the fabrication of modulated submicrometer gratings in photoresist.High diffraction efficiency requires optimized recording conditions, which are obtained by the use of an on-axis continuous surface-relief grating for the generation of the object beam. The optimized phase function is copied into the resist layer by means of a self-aligned two-step recording process with an intermediate copy in a volume photopolymer hologram. As a result, we demonstrate high carrier frequency surface-relief off-axis fan-out gratings for illumination in transmission with visible light.  相似文献   

17.
Interferometric lithography (IL) is a powerful technique for the definition of large-area, nanometer-scale, periodically patterned structures. Patterns are recorded in a light-sensitive medium, such as a photoresist, that responds nonlinearly to the intensity distribution associated with the interference of two or more coherent beams of light. The photoresist patterns produced with IL are a platform for further fabrication of nanostructures and growth of functional materials and are building blocks for devices. This article provides a brief review of IL technologies and focuses on various applications for nanostructures and functional materials based on IL including directed self-assembly of colloidal nanoparticles, nanophotonics, semiconductor materials growth, and nanofluidic devices. Perspectives on future directions for IL and emerging applications in other fields are presented.  相似文献   

18.
Abstract

A new method is presented to record multiple fractional Fourier transform holograms by use of a holographic lens. With holographic lenses, several fractional Fourier transform holograms of different objects can be recorded in a simple way, and images of these recorded objects can be reconstructed in different positions and directions in three-dimensional space. In this paper, the theory and characteristics of the hologram recorded using the holographic lens are analysed. Using this method, a multiple fractional Fourier transform hologram was fabricated, with satisfactory results.  相似文献   

19.
径各平方贝赛尔函数调制高斯光束的焦移   总被引:2,自引:2,他引:0  
给出变量为径向平方的贝塞尔函数调制的高斯光束(QBG光束)通过ABCD聚集光学系统的轴上光强分布公式,对QBG光束通过薄秀镜聚集系统的轴上光强分布及焦移进行了研究,得到相对焦移满足的三次方程和解析解,给出详细的数值计算结果并进行了分析讨论。  相似文献   

20.
Lim Y  Hahn J  Lee B 《Applied optics》2011,50(34):H68-H74
We present phase-conjugate holographic lithography with a hologram recorded by a digital micromirror device (DMD) and a telecentric lens. In our lithography system, a phase-conjugate hologram is applied instead of conventional masks or reticles to form patterns. This method has the advantage of increasing focus range, and it is applicable to the formation of patterns on fairly uneven surfaces. The hologram pattern is dynamically generated by the DMD, and its resolution is mainly determined by the demagnification of the telecentric lens. We experimentally demonstrate that our holographic lithographic system has a large focus range, and it is feasible to make a large-area hologram by stitching each pattern generated by the DMD without a falling off in resolution.  相似文献   

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