共查询到20条相似文献,搜索用时 31 毫秒
1.
We propose a method to produce a hard copy of a three-dimensional (3-D) image by a conventional high-resolution printer. Parallax information is recorded on a transparency by the printer, and a reflection-type holographic screen composed of a number of small elementary holograms is attached on the transparency. The quality of the 3-D image is investigated, and the characteristics of the proposed method are described. 3-D image of full-parallax is experimentally produced using a laser printer. 相似文献
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《中国光学快报(英文版)》2020,(6)
In this Letter, a method for shape visualization of small objects(microscopic) in the form of a hologram is presented. It consists of a standard optical set-up for small object registration(i.e., stereoscopic or biological microscope). The focus stacking technique is used to obtain a series of images with increased depth of field and on them a shape reconstruction procedure(structure from motion, SfM) is made. With use of a dense cloud of points, a sequence of parallax-related images suitable for Geola's digital holographic printing is generated. The holographic printer produces single-parallax holographic(full three-dimensional) images of real or virtual objects. 相似文献
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We propose a new multiple-exposure scheme for full-color full-parallax holographic three-dimensional (3D) printer, in which two of three primary-color holograms are exposed at the same location on the recording medium. In this paper, the optimal combinations of colors for multiple exposure are experimentally derived. In addition, it is shown that the proposed method enables higher brightness, better color reproducibility, and high resolution through the experiment of recording and measurement of color-chart holographic stereogram. 相似文献
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A holographic system has been developed to visualize a three-dimensional fluid flow. The system consists principally of a thermoplastic film, a monochrome video camera, a microcomputer with image-processing capability and a printer. The system makes it possible to measure a slow flow. Two examples of such, the bimodal and mixed-mode convection flows within a Bénard cell, are presented. 相似文献
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数字微镜器件在视频全息中的应用 总被引:6,自引:2,他引:4
为研究数字微镜器件在视频全息中的应用,探讨了基于数字微镜器件的全息编码方法。基于数字微镜器件的微观物理结构,讨论二维离散微镜像素结构、开态微镜列的闪耀光栅特性和脉宽调制的微镜偏转工作原理。将数字微镜器件分辨力、微镜尺寸、间隔、旋转角度、参考光入射角以及衍射条件等因素结合到计算全息编码中,提出干涉面抽样方法、相位补偿技术和无偏置二元全息编码方法,使产生的计算全息图适应数字微镜器件独特的空间光调制特性和计算视频全息的要求。实验表明,该方法调整了重构物光波的衍射方向,集中了衍射光在重构像中的分布,增加了成像清晰度和光能有效利用率,提高了全息编码效率。 相似文献
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A system of evaluating the microstructure of a holographic plate (for example; a light sensitive plate in dichromated gelatin (DCG) or photoresist emulsion) with economical measuring equipment is described. We observe the holographic plate with a microscope and CCD camera with a PC 586 computer. With the information from grey levels of the scanning image we obtain four film quality characteristics. We can scan the full size of the plate to obtain the macro-pattern. We can also select other magnifications of the local pattern. The apparatus has particular use in the detection of micro-particles of a microstructure. 相似文献
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Study on 3-D arc plasma fields with holographic interferometry 总被引:2,自引:0,他引:2
In this paper,serveral temperature(refractive index)fields which are de-scribed by different kinds of functions are reconstructed by computer simulations based onholographic tomography theory.The obtained results are compared and analyzed.We de-signed a special multibeam holographic system in which the disturbance from the intense arclight can be filtered.With the system multidirectional holographic interferograms of arc fieldscan be taken simultaneously.We also calculate the quantitative distributions of temperature,the number density of particles and ionicity at a typical section of the argon arc field from theexperimeantal data. 相似文献
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二维光学沃尔什—哈特曼变换 总被引:1,自引:1,他引:0
从光学变换的基本方程出发,分析了变换所需的空间横向调制型全息透镜的相位误差,提出用计算机产生全息图和光学全息相结合的方法产生高精度的二维变换全息透镜.在实验上实现了二维32序的光学沃尔什-哈特曼变换,实验结果与理论计算一致. 相似文献
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CRT-LCLVandphotorefractivecrystalBSObasedreal-timejointtransformcorrelatorFUXiaoli;LIYulin;ZHANGHai;WANGDayong(XianInstituteo... 相似文献
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This paper describes the applications of a multipurpose holographic device in optical networks with Coarse and Dense Wavelength
Division Multiplexing (CWDM/ DWDM) technologies. In its basic structure, it can operate as a tunable wavelength filter, wavelength
multiplexer or λ router. By using a more complex structure, the device works as OADM (Optical Add Drop Multiplexer) or OS (Optical Switch).
Some simulations of the basic devices, from the optical transmission point of view, are made to match the transmission parameters
for the application in optical networks. Performance parameters of the device, like switching time, losses, cross-talk or
polarization insensitivity are analyzed and compared with other multiplexing or switching technologies. To complete the review
of these components, a study of computer generated holograms (CGH) design is carried out. The results are used in the design
of holographic devices to perform different applications: in Metro networks, where a design of a holographic device with wavelength
conversion and routing is analyzed, or, in Access Networks like a tunable filter or demultiplexer in Fiber to the Home/Business
(FTTH/FTTB) topologies. 相似文献
14.
Optical holographic interference fringe patterns on rods and bars vibrating in ultrasonic resonance (standing waves) are predicted by computer simulations. The simulations are based on a combination of finite element calculations with calculations based on the theory of holographic interference fringe generation. The hypothetical fringe patterns are then compared to holographic fringe images obtained by the experiment (time average holograms). The holographic arrangement and the mechanical part of the ultrasonic system (transducer, horn and specimen) were fixed on a commercial rigid optical table supported on air bags to isolate it from ground vibrations. Thus it is shown that the scope of the study can be reached with a minimum of experimental effort, i.e., with basic laser optical equipment. It is shown that provided the system operates in the desired mode, good agreement between the theoretical and the real image is given. Finally examples of the possible influence of defects or of parasitic modes of vibration on the appearance of the fringe patterns are given. 相似文献
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The low space-bandwidth product of simple computer generated filters is increased by holographic techniques to form holographic filters which may be combined with coherent optical processing to restore blurred photographs. 相似文献
16.
It is shown theoretically and verified experimentally that by writing a low spatial frequency Ronchi grating by a computer and printing two copies of it on two transparencies by a printer, the modulation transfer function (MTF) of the printed image can be evaluated by measuring the transmittance of the superimposed gratings in a moiré fringe spacing. Application of the technique is quite simple and the results are reasonably reproducible. The technique does not require a high sensitive intensity detector and a very narrow slit for transmission scanning. Also, the presented technique can be applied to other imaging systems. 相似文献
17.
Yoshio Hayasaki Maki Nishitani Hidetomo Takahashi Hirotsugu Yamamoto Akihiro Takita Daichi Suzuki Satoshi Hasegawa 《Applied Physics A: Materials Science & Processing》2012,107(2):357-362
In holographic femtosecond laser processing, diffractive parallel pulses are distorted by phase discontinuities and mutual
interference between the neighborhoods in the reconstructed image of a Fourier computer-generated hologram when the interval
is smaller than the beam diameter. We investigated holographic fabrication on a glass surface using parallel pulses with different
intervals. We found the closest parallel pulses with sufficient separation to avoid mutual interference in holographic femtosecond
laser processing. The minimum interval was 2.8 times larger than the diffracted beam diameter. The experimental results were
also supported by a computer simulation. Our findings will be very useful in the design of holographic laser processing systems. 相似文献
18.
《中国光学快报(英文版)》2017,(12)
A computer generated holographic stereogram based on the wavefront recording plane(WRP) is presented. A WRP closed to the parallax image plane is introduced to record the complex amplitude in a small region for each point in the parallax image. By using three times of fast Fourier transform(FFT) to execute the Fresnel diffraction calculation between the WRP and the holographic stereogram plane, the object wave contributing to the hologram pattern can be achieved. The computation complexity of the proposed approach is dramatically reduced. The results show that the calculation time can be decreased by more than one order of magnitude. 相似文献
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Hideki Funamizu Tsuyoshi KatoYoshihisa Aizu Yukihiro Ishii 《Optics Communications》2012,285(24):4987-4992
We present the correction of a quadratic phase error in two-wavelength digital holographic interferometry using laser diodes. This phase error arises from numerical reconstructions of wavefronts from digital holograms based on the Fresnel diffraction integral. To correct the quadratic phase error, it is numerically produced by computer on the basis of the theoretical prediction and is subtracted from the phase difference map in two-wavelength digital holographic interferometry. Experimental results show that the method of correction in this paper is useful for two-wavelength digital holographic interferometry using laser diodes. 相似文献