基于计算全息的全视差合成全息研究

文中进行了一种新型三维全息图的制作方法研究,该方法基于计算全息原理,与合成全息相结合,实现激光三维全息图的直写打印制作。首先进行了菲涅耳计算全息图的实验,表明计算全息与合成全息结合的可行性与合理性。然后根据合成全息原理与计算全息原理对三维模型进行采样和图像变换处理,再计算出相应的菲涅耳计算全息图,借助数字全息激光打印系统完成三维全息图的拍摄,在激光下进行光学再现,最后对再现结果进行了分析与讨论。     

基于多视差立体显示的数字合成全息技术研究

合成全息图利用多视差图像实现立体显示,并可通过分区曝光实现大面积制作。介绍了数字合成全息的原理及其实验系统,针对其制作过程中的两种图像采样方式,研究了图像的分割和重组原则。通过对单元全息图合成拍摄中图像重叠投影的分析,基于非成像光学理论设计制作了能实现这一功能的透镜,并借助光学软件对其进行了仿真。最后利用所设计的透镜进行了合成全息实验,结果表明,利用所设计的重叠投影透镜和适当的图像处理方法,能合成出轮廓清晰、立体感强的全息立体图。     

大型菲涅耳人像全息图的制作

研究了用于三维(3D)展示的大面积拼接菲涅耳合成全息图的制作方法。在研究菲涅耳全息原理与合成全息原理的基础上,解决了菲涅耳合成全息图在再现图像时再现窗口与观察视场不符的问题。利用激光作为记录和再现光源,进行了全息图拍摄实验,实现了大面积、大景深、高质量的三维人像合成全息图的制作。     

计算集成平板周视彩色全息图

提出计算机和光学联合制作平板周视全息的方法,通过计算得到集成菲涅耳环带全息图,利用环带全息图的再现像作为记录目标进行光学全息的拍摄,实现集成平板周视彩色全息图。详细分析了集成平板周视彩色全息原理,通过实验进行了验证。该方法增强了体视全息显示的灵活性,提高了平板周视彩色全息图的计算速度。     

动感像素全息母版图案的设计制作研究

本文介绍了一种新颖的数码像素全息高速拍摄装置来实现全息母版的制作。提出和介绍了运用Photoshop软件一些特殊的图像处理功能设计制作动感像素全息图的方法,并结合多种防伪技术,使产生的图案具有不可仿制的图形畸变特点,并列举了设计实例。     

计算机与光学方法相结合的彩色彩虹全息术

提出了计算机制全息与光学全息相结合制作彩色全息图的彩色彩虹伞息术.通过计算机对彩色图像进行自动分色,制作红、绿、蓝3幅丰计算全息图H1,以H1的再现像为对象,用激光制作彩色彩虹全息图H2,用白光再现获得彩色再现像.该方法把汁算机制全息与传统的光学全息相结合,发挥了计算全息与光学全息的优势.在全息图的计算中采用了快速傅里叶变换,加快了计算速度.给出了理论分析和实验结果.     

一种数字化的全息透镜制作方法

提出了一种采用并行激光直写技术的数字化全息透镜制作方法,先对离轴全息透镜进行理论模拟,得到条纹分布的数字图像,根据激光直写系统的光学参数,对生成的全息透镜模拟图像进行缩放处理,然后分块拼接曝光,实验得到了尺寸为3.1 mm×3.1 mm的正方形离轴全息透镜,最小条纹周期为1.1 μm,在532 nm激光照射下,透镜焦距为6.2 mm,最大空频处一级衍射光的衍射角为5.9°。本方法为制作全息透镜提供了一种有效地新方法。     

二元光学元件在模压全息母板拍摄中的应用

物光和参考光的均匀性对彩虹全息图的拍摄,特别是模压全息防伪标记母板的拍摄有重要意义。采用经傅里叶变换设计的二元光学元件,通过光学变换来实现这种光强分布的均匀性,不失为一种有效的方法。     

计算机制一步彩色彩虹全息的研究

针对现有的彩色全息技术中存在的制作过程复杂、色串扰、技术条件要求高等问题,提出了一种计算机制一步彩色彩虹全息技术。该技术将光学一步法彩虹全息技术和多次曝光彩色全息技术相结合,首先根据线全息图理论,确定每个物点的线全息图在整个彩虹全息图中的区域范围,并计算线全息图,然后将每个物点的线全息图相加,直接获得计算机制一步彩虹全息图,大大减少了全息图的计算量。在此基础上,分别计算彩色物体的红、绿、蓝三分色计算全息图,并合成为彩色彩虹全息图,用白光再现获得真彩色全息再现像,大大简化了彩色彩虹全息图的制作过程、降低了技术条件要求,充分发挥了计算全息简单、灵活、方便的优点。给出了理论分析和实验结果。     

激光直写技术应用于烫金箔隐形图像上的研制

用电子束逐行扫描方法刻蚀衍射光学元件的浮雕结构精度高而速度低。提出了一种采用逐点激光直写浮雕位相结构方法来产生具有隐形图像反射二元整形元件,指出用方点光刻位相结构有利于衍射效率的提高。在激光烫金箔上制作具有隐形图像功能的二元整形位相结构,再现图像的 1级衍射效率可达12％—21％,给出了实验结果。     

Infared holographic optical elements with applications to laser material processing

Reflective holographic elements replayed at the 10.6 μm wavelength of the CO2laser can generate wavefronts that cannot be obtained using conventional optical elements. One proposed application is to use the projected holographic real image for laser materials processing, such as cutting or soldering. Three methods are discussed for producing the required holograms: computer generation, direct recording at 10.6 μm, and indirect recording in the visible. Results are presented on image intensity roll-off and aberrations introduced in image reconstruction.     

LC-SLM的光学调制特性及其在全息中的应用

液晶空间光调制器是实时光学信息处理中的重要器件,本文分析了液晶空间光调制器的光学调制特性及其目前在全息领域的主要应用.并根据液晶空间光调制器实时再现计算全息图的原理,提出利用计算全息技术得到单元合成全息图阵列,通过计算机控制向液晶空间光调制器输出合成全息图序列进行实时光电再现进而实现合成全息动感的方法,分析了基本原理和实现方法并给出了相应实验结果.     

多通道综合全息术及在材料性能检测中的应用研究

自激光问世以来,应运而生的激光全息干涉计量术得到迅速发展,应用于许多领域。文中提出并实现了干涉条纹载波法一时间平均多通道综合全息术,这种技术综合应用了多种全息术并用光路通道转换器调制平面参考光波实现多通道全息图记录,再现时可同时观察所有通道的原始像。文中给出了多通道综合全息术有关的理论分析和在材料性能检测中的应用实例,给出了温度变化对叶片试件振动影响的实测结果,这一研究对叶片的设计优化具有实用意义。     

Microwave holographic interferometry

Microwave holography is an extension of the optical holography to the microwave field. In fact, by using a well-known characteristic of the holographic process, it is possible to record the hologram at frequencies very far from the optical region (microwave) and to reconstruct a visible image by laser light. This paper describes the experimental apparatus and the technique used for obtaining a satisfactory optical wave reconstruction from microwave holograms. The resolving power of the system which was experimentally tested, and visible images of microwave transparencies and of a back scattering object are given. As an alternative application of the microwave holography together with the optical wave reconstruction, in this paper, extension of holographic interferometry to the microwave region is suggested, and the visible image of a deformed object crossed by fringes due to microwave interference is also shown. This technique can find applications, for instance, in the mapping of the earth's deformations or in that of the tides. Different aspects of the microwave holographic interferometry have been also discussed.     

全光纤全息技术的研究与实现

本文对全光纤全息系统的原理、器件选择和实现手段进行了研究,采用光纤迈克耳逊干涉仪稳相结构建立了可应用于多种全息结构的全光纤全息系统,拍摄出了具有较为清晰再现象的全息图。本文结果证实了光纤全息系统在把全息技术用于现场实用方面的巨大潜力,为全息技术的进一步研究奠定了基础。     

Multi-Spectral Holographic Three-Dimensional Image Fusion Using Discrete Wavelet Transform

We present multi-spectral holographic three-dimensional image fusion using the discrete wavelet transform (DWT). The fusion results are compared with those of the Gaussian and Laplacian pyramid fusion methods. The advantage of the DWT over other methods is that it has more flexibility in controlling high frequency components as well as low frequency components, which improves the fused image quality. A wavelength tunable solid-state pumped laser is used to record up to 11 holograms with wavelengths from 567 to 613 nm. We present the fused reconstructed holographic images including multi-spectral fused images from the recorded multiple holograms. Fused multi-wavelength reconstructed holographic images provide multi-spectral information about the objects     

9A9--Pulsed laser holograms

The limited coherence of most pulsed lasers is the principle difficulty in making pulsed holograms. This paper describes techniques used for the production of quality holograms of back lighted subjects, using ordinary pulsed lasers. The arrangements used achieve a temporal and spatial matching of the scene and reference beams to the degree required by the laser coherence cell. Techniques are described which prevent the destruction of the spatial match when using a diffusing screen. The use of lenses to permit the recording of large subjects on small holograms with limited pulsed energy is described. The limitations on subject motion are described. Experimental examples of the techniques are illustrated by holographic recordings of bullets in flight. The technique of double exposure holographic interferometry is also illustrated.     

用全息分色法制作彩色全息图

通过使用三张编码全息片和三种滤光片,用白光将彩色正片的红、绿、兰三色信息记录在一张或两张全息片上。用单色激光同时再现出记录的三种颜色信息的光强分布,并将它们记录在同一张全息片上作成彩色全息图。本方法的显著优点是消除了影响彩色全息图质量的激光斑纹及提高了彩色全息图制作中的光功率利用率。     

Micro systems engineering and digital holographic flash memory

A model of an active distributed computing medium is proposed that records and plays back a signal (a two-dimensional array of numbers). This medium represents a 3D integrated circuit, designed on the electronic nanoelement base, that employs the principles of optical holography; however, the operating signal in this medium is an electrical digital signal rather than a light signal. Requirements on the structure and the properties of this medium, as well as on its elements and methods of their connection, are formulated for a more detailed analysis of the information capacity and efficiency of such a computing medium. Unlike holographic optical disks, this medium can play the role of not only external read only memory (ROM), but also high-speed flash memory with a capacity on the order of 200 GB and a data input-output rate of up to 10⁶ GB/s for a working volume of 1 cm³. This medium, in view of its inherent associative properties of optical holographic memory, could perform, in addition to the function of flash memory, some functions of optical holograms, such as pattern recognition; however, in view of a different element base, it would be more reliable and noise-immune.