Quantization has very good effect and reductions to as few as 3 bits in each. In this case the drawback is that precisely controlled subwavelength translations of the sample or of a reference mirror are required. Random noise is also added to the multiplexed hologram. In order to reconstruct the threedimensional features of objects is broadly used the phase shifting technique in digital holography 31, the images resulting from this process withdraw the zero order term and the conjugated image of the object, that are usually seen in dh. Phaseshifting digital holography which is available simply with single holograms without any special phaseshifting device is proposed. Effects of quantization in phaseshifting digital holography osa.
Furthermore, the design of phaseshift digital holography psdh gives. This method has been coupled with microscopy 1 for applications such. The influence of bitdepth limitation in quantization has. Digital holography dh has emerged as one of the most effective coherent. Digital holography offers a means of measuring optical phase data and typically delivers threedimensional surface or optical thickness images. Other readers will always be interested in your opinion of the books youve read. Investigation on temporal phase shifting in digital shearography during transient process paper 152249 authors. Mirror with pzt half mirror phase shift half mirror figure 53. However, no simultaneous reconstruction of absorption and phase shifting distributions from a single terahertz in line hologram has yet been reported. Effects of quantization in phaseshifting digital holography, appl. The timeaveraged complex amplitude of fresnel diffracted field due to a vibrating object was obtained by using. The results based on the digital in line holography show that the two fourstep phase shifting algorithms possess different sensitivity to the phase shifting errors, and the preferable one. Freeviewpoint images captured using phaseshifting synthetic aperture digital holography tatsuya nakatsuji and kyoji matsushima department of electrical and electronic engineering, kansai university, yamatecho 3335, suita, osaka 5648680, japan corresponding author.
With phaseshifting holography, it is possible to obtain the two quadratures of the field even though the conjugate image alias and the true image overlap, because aliases can be removed by taking image differences. In ref 21, the authors studied the effect of quantization in phase shifting digital holography and it was shown that the use of 4 bits for hologram quantization is adequate for visual. Comparison of digital holography and transport of intensity for. We vary bit depths of phaseshifted holograms in both numerical simulation and experiments and then derived the complex. A new estimation method for twosteponly quadrature phase. On fresnelets, interference fringes, and digital holography.
A new method for threedimensional image formation is proposed in which the distribution of complex amplitude at a plane is measured by phase shifting interferometry and then fresnel transformed by a digital computer. The optical phase of the reference beam is shifted from one sampled interferogram. The required intensity quantization level is helpful for selecting a digital image sensor. Quantization noise and its reduction in lensless fourier. Small amount of storage memory is needed in the encoding and decoding processes. It is free from tedious photographic processing and delivers threedimensional distributions of both amplitude and phase quantitatively. Introduction in digital holography, holograms are recorded using an image sensor such as ccd cameras, and reconstruction of images of the object is performed by a computer. Digital holography dh has emerged as one of the most effective coherent imaging technologies. Introduction digital holography dh is a measurementtechniquebased on an interferometricprinciple, whichenables the recovery of both the amplitude and phase of a wavefront. In digital holography, one of the most important tasks is to eliminate the undesired zeroorder and twin image to obtain a high quality reconstruction. The decoded hologram is real and can be displayed on a spatial light modulator. For example, psfs quantized at discrete levels around the wrp can be. Superresolution imaging method using phase shifting digital.
Encryption is performed by utilizing the fresnel diffraction pattern of a random. To perform phase shifting digital holography psdh, several holograms have to be recorded, each with the phase of the reference wave shifted to different states. Uncertaintymanaged phaseshifting digital holography. Oneshot phaseshifting digital holography based on the. For hologram recording a conventional holographic setup can be used, as long as a phase shifting element is included in the optical path of the reference beam see fig.
In the paper, they have presented a new application of digital holography for phase contrast imaging. Suppression of the zeroorder and twin images by phaseshifting digital holography allows efficient use of the pixel array 24. Strategies for reducing speckle noise in digital holography. Phaseshifting digital holography is a digital measurement technology of a complex optical field profile that uses focal plane array detectors without the loss of bandwidth. Comparative study of scalar and vector quantization on. In digital holography holograms are recorded by a ccd and image reconstruction is performed by a computer. A phaseshifting interferometer records the phase and amplitude information generated by a threedimensional object at a plane located in the fresnel diffraction region with an intensityrecording device. Phaseshifting interferometry avoids the need to track the location of the. Digital holography refers to the acquisition and processing of holograms with a digital sensor array, typically a ccd camera or a similar device. We have recently studied the effects of reduction of bitdepths in.
Parallel phaseshifting digital holography using lcosslm. Wave front reconstruction by means of phaseshifting digital. Effects of quantization in phaseshifting digital holography. Nov 29, 20 we compare the influence of intensity quantization in ppsdh with that in the conventional phase shifting method. The compression method is based on delta modulation and row decimation. In the integrated phase shifting scheme, the phase shifts are generated by a reference mirror moving with a uniform velocity, and sequential phaseshifted holograms are captured. Phaseshifting digital holography is widely used to determine the phase as well as the amplitude of the objects wave 1, 2. It has been known that the accuracy of phase shifting digital holography is limited mainly by the phase tolerance of reference. We discuss quantization effects of hologram recording on the quality of reconstructed images in phaseshifting digital holography. Signal processing challenges for digital holographic video.
Threechannel color digital holography has been demonstrated 10. Openaccess holographic data are selected and characterized as references for the experimental analysis. Image rendering, or reconstruction of object data is performed numerically from digitized interferograms. Yamaguchi, threedimensional microscopy and measurement by phaseshifting digital holography, selected papers from fifth international conference on correlation optics, o. We identify challenges in hardware and software and collect a set of.
Traditionally, interferograms were measured by locating the center of a fringe and then tracing along the fringe. Phase shifting digital holography allows elimina tion of zeroorder and twinimage components even in onaxis arrangemen t 68. Therefore, the concept of digital holography is a promising approach to 3dtv. Introduction digital holography has many versatile applications, including microscopy 1, phase contrast 2, 3d displays 3, tomography 4, and terahertz imaging 5. Freeviewpoint images captured using phaseshifting synthetic. In twostep quadrature phaseshifting holography, two phaseshifting onaxis holograms with a zero phase shift and a p2 phase shift are achieved, as follows. The purpose of this third edition is to bring together in a single book descriptions of all tests carried out in the optical shop that are applicable to optical components and systems. The technological developments of digital sensors and optical elements have made dh the primary. Computer simulation and experimental results have been performed to verify the effectiveness and feasibility of our proposed method.
Strategies for reducing speckle noise in digital holography nature. Request pdf phaseshifting digital holographic data compression modern holography for 3d. Superresolution imaging method using phase shifting. We vary bit depths of phaseshifted holograms in both numerical simulation and experiments and then derived the complex amplitude, which is subjected to fresnel transformation for the image reconstruction. Javidi, a companding approach for nonuniform quantization of digital holograms of threedimensional objects, optics express 1412, 512954 2006.
Chapter 5 phaseshifting digital holography principles and. Digital holography, image reconstruction technique, interferometric imaging, phase measurement. As a side effect, the zeroorder term and the twin image can be eliminated in the reconstructed image. The results based on the digital inline holography show that the two fourstep phaseshifting algorithms possess different sensitivity to the phaseshifting errors, and the preferable one. Offaxis and in line holographic schemes have their advantages and disadvantages 14. The best known example is phaseshifting digital holography 64, where. This technique enables the measurement of both amplitude and phase, useful for quantify. We propose integrated phase shifting digital holography using statistical approach.
The authors present a parallel phaseshifting digital holography as a digital imaging technique for recording and reconstruction of threedimensional object. The phase shifting or phase stepped digital holography process entails capturing multiple interferograms that each indicate the optical phase relationships between light returned from all points on the illuminated object and a controlled reference beam of light. Strategies for reducing speckle noise in digital holography ncbi. Wave front reconstruction by means of phase shifting digital in line holography. More exposures can be taken to improve noise robustness. Digital holography for quantitative phasecontrast imaging. Digital holography, phase shifting interferometry, oneshot hologram 1. Effects of 2d phase unwrapping and flat quantization on compression performance are also reported. We propose integrated phaseshifting digital holography using statistical approach. Optical scanning holography can generate holographic images of fluorescence 9. Setup for microscopy using phaseshifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5. The best known example is phaseshifting digital holography, where generally at least 3 exposures are needed to unambiguously retrieve the complex amplitudes cf.
Encoding and decoding processes are low in complexity, enabling realtime operation. To this end, we derive a method for retrieving the amplitude and phase of the object wave through a. The experimental results of digital hologram acquisition and reconstructions are given for a standard usaf test pattern. Thelowest quantizationonecanachieve directly is 1bit per pixel, the binary hologram. Dec 14, 2010 a method of a digital holography based on the use of a selfimaging of the phase element is presented and assessed in terms of image quality and resolution.
A lowpower headmounted phaseonly holographic display by. The nondestructive, noncontact, threedimensional evaluation of optical glass has been important to the manufacturing of highprecision optical components. Phd and mphil thesis classes mural maynooth university. Fast method of recovering referencewave intensity in two. We next propose a versatile pcmpoh codec with progressive quantization that can adapt to slmdynamicrange and available. By collecting two frames of interference between object and reference fields with identical reference phase, one can estimate the lateral motion that occurred between frames using the crosscorrelation. Whether youve loved the book or not, if you give your honest and detailed thoughts then people will find new books that are right for them. Highresolution quantitative phase contrast microscopy by digital holography christopher j. This project was supported by the research fund for the doctoral program of. A method for compressing optical scanning hologram by 64 times has been developed. Phaseshifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination.
Single shot digital holography using iterative reconstruction. Demonstration of compression ratio of over 4000 times for. We propose and demonstrate light in flight recording by parallel phase shifting digital holography to obtain a motion picture of ultrashort light pulse propagation free from unwanted images, which are a zerothorder diffraction image and a conjugate image, by phase shifting interferometry with a singleshot exposure. In phaseshifting digital holography, darakis et al. Lightinflight recording by parallel phaseshifting digital. Interferometry is applied in a wide variety of fields, including astronomy, fiber optics, optical metrology, oceanography, seismology, quantum mechanics and plasma physics. Dynamic digital holography for recording and reconstruction.
In addition, the phase shifting errors may cumulate or not according to different phase shifting techniques, and both cases are considered in this paper. The following challenges in the design of holographic display impact signal processing requirements. In one of our previous works the preliminaries of an all digital holographic approach to 3dtv were given. Digital holography represents a novel media which promises to revolutionize the way the users interacts with content. Image reconstruction only by phase data in phaseshifting. Lowcomplexity compression of holograms based on delta modulation. We have recently studied the effects of reduction of bit depths in. Gabor in line digital holography in imaging concealed objects 12. A method and system for encrypting multidimensional information utilizing digital holography is presented.
Development of an optical heterogeneity evaluation system. Phaseshifting digital holographic data compression request pdf. Narayanamurthy, indian institute of space science and technology india. Amongst the various dh methods, digital phaseshifting interferometry stands out. Wave front reconstruction by means of phaseshifting. Digital gabor holography, without separate reference. In order to achieve highprecision nondestructive evaluation of optical heterogeneity, we develop a versatile evaluation system using the parallel phase shift digital holography, which enables measurements of the optical path differences. Terahertz inline digital holography of dragonfly hindwing. Suppression of the zeroorder and twin images by phase shifting digital holography allows efficient use of the pixel array 24. Yamaguchi, effects of quantization in phaseshifting digital holography, applied optics 4416, 12161225 2005. The method can reconstruct an arbitrary cross section of a threedimensional object with higher image quality and a wider viewing angle than from conventional digital holography.
In the integrated phaseshifting scheme, the phase shifts are generated by a reference mirror moving with a uniform velocity, and sequential phaseshifted holograms are captured. We vary bit depths of phaseshifted holograms in both numerical. May 15, 2006 we present a technique for phase shifting digital in line holography which compensates for lateral object motion. The best known example is phase shifting digital holography, where generally at least 3 exposures are needed to unambiguously retrieve the complex amplitudes cf. While there are several methods for zeroorder and twin image elimination or suppression, phaseshifting holography psh 1, 2, 3 has been the most widely used technique for this task. Phaseshifting digital holography allows elimina tion of zeroorder and twinimage components even in onaxis arrangemen t 68. Superresolution imaging method using phaseshifting digital lensless fourier holography luis granero 1, vicente mico 2, zeev zalevsky 3, and javier garcia 2 1aido technological institute of optics, color and imaging, c nicolas copernico 7, 46980, paterna, spain. It has been known that the accuracy of phaseshifting digital holography is limited mainly by the phase tolerance of reference. In the field of coherent metrology, the effects of quantization in phaseshifting interferome try 14,15, fringe analysis 1, and phaseshifting digital holography psdh 16, 17 have been. Effect of phaseshifting error on deformation evaluation. Freeviewpoint images captured using phase shifting synthetic aperture digital holography tatsuya nakatsuji and kyoji matsushima department of electrical and electronic engineering, kansai university, yamatecho 3335, suita, osaka 5648680, japan corresponding author.
Quantization noise and its reduction in lensless fourier digital. Techniques of digital holography are improved in order to obtain high. Phase shifting digital holography is a digital measurement technology of a complex optical field profile that uses focal plane array detectors without the loss of bandwidth. Highresolution quantitative phasecontrast microscopy by. This book is intended for the specialist as well as the nonspecialist engaged in optical shop testing. The technique uses a ccd camera for recording of a digital fresnel offaxis hologram and a numerical method for hologram reconstruction. There is currently a great deal of research being done in optical engineering.
Also see 20 for a survey on quantization in holography. A new method for threedimensional image formation is proposed in which the distribution of complex amplitude at a plane is measured by phaseshifting interferometry and then fresnel transformed by a digital computer. A phase shifting interferometer records the phase and amplitude information generated by a threedimensional object at a plane located in the fresnel diffraction region with an intensityrecording device. Setup for microscopy using phase shifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5. Effect of intensity quantization level in parallel phase. The technique is implemented by inserting a phaseshifting array device consisting of array of 2.
Phase shifting digital holography has been used for the study of vibrating objects. Digital holography applications in ophthalmology, biometry. The reconstructed wavefield contains phase and intensity distributions, which means it is full 3d, exhibiting such effects as depth and parallax. Principles and techniques of digital holographic microscopy. In one of our previous works the preliminaries of an alldigitalholographic approach to 3dtv were given. A significant constraint of digital holography is the pixel count and resolution of the imaging devices. The method simultaneously provides an amplitudecontrast image and a quantitative phase contrast image. Phase shifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination. Digital holographybased security schemes book chapter.
You need an ereader or compatible software to experience the benefits of the. Multiexposure methods on the other hand, consist of taking several measurements in succession. However, no simultaneous reconstruction of absorption and phaseshifting distributions from a single terahertz inline hologram has yet been reported. Gabor inline digital holography in imaging concealed objects 12. In particular, holograms generated by the phaseshifting digital holography method are tested, and the compression is performed by scalar uniform and adaptive quantization and by vector. Interferometry is the technique of superimposing interfering two or more waves, to detect differences between them. The image quality and resolution limits of phaseshifting. Abstract we discuss quantization effects of hologram recording on the quality of reconstructed images in phaseshifting digital holography.
Signal processing challenges for digital holographic video display. Jay krishna ananad, indian institute of space science and technology india. Optics and photonics for advanced dimensional metrology. We next propose a versatile pcmpoh codec with progressive quantization that can adapt to slmdynamicrange and available bitrate, and features perpixel ratedistortion control to achieve. Motion compensation and noise tolerance in phaseshifting.