Phase shifting is utilized to obtain a clear reconstructed object wave from a rough surface texture. Thus, there is no need to generate a macroscopic interference pattern. Highresolution quantitative phasecontrast microscopy by. The optical phase of the reference beam is shifted.
Digital holography using a laser pointer and consumer digital. Phaseshifting is utilized to obtain a clear reconstructed object wave from a rough surface texture. Its main limitation that is caused by much lower resolution of ccds than photographic materials has been substantially overcome by phase shifting digital holography that reduces the spatial frequency of hologram by employing the inline setup and directly evaluates complex amplitude at the ccd plane to eliminate the conjugate and zeroth order. Optical scanning holography osh 1,2 is one of the most effective techniques for capturing a complex hologram of a physical scene. We vary bit depths of phase shifted holograms in both numerical simulation and experiments and then derived the complex. Setup for microscopy using phaseshifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5. Twosteponly quadrature phaseshifting digital holography faculty. Phaseshifting digital holography is widely used to determine the phase as well as the amplitude of the objects wave 1, 2. So they use holographic displays to show the hologram, depending on a high level of computation. Digital holography refers to the acquisition and processing of holograms with a digital sensor array, typically a ccd camera or a similar device. Conventional methods of quadrature phaseshifting holography require two holograms and either intensity distribution of the reference wave or. We discuss quantization effects of hologram recording on the quality of reconstructed images in phase shifting digital holography. Highresolution quantitative phasecontrast microscopy by digital holography christopher j.
Introduction first experiments in numerical reconstruction of optical holograms date back to 196070th. Holography 1 background the word hologram was coined from the greek word \holos which means whole, because the recorded hologram contains all the information of the image eld. Though digital inline holography is fazed by the reconstructed twin images, people try to apply it to many different areas. Compared with offaxis holography, traditional inline holography proposed by gabor shows two remarkable traits. Phaseshifting digital holography in image reconstruction. Wave front reconstruction by means of phaseshifting digital inline holography. Digital holography offers a means of measuring optical phase data and typically delivers threedimensional surface or optical thickness images. Digital holography using a laser pointer and consumer digital camera report date. The influence of bitdepth limitation in quantization has. Optical measurement of twodimensional surface roughness and texture using a. Yokota, surface shape measurement by dualwavelength phaseshifting digital holography, fringe 2005, proc. Phase shifting digital holography is applied to measure the shapes and positions of rough surfaces from the averaged conjugate product of the reconstructed complex amplitudes, named complex.
That allows obtaining enough information for single and full parallax digital holograms 1, 2. Kim university of south florida, department of physics, 4202 e. Additionally, the interference phase in dhi can be determined without sign ambiguity. The phase of the averaged product at the object plane provides the shape of the surface, whereas the peak position of the modulus with. Improvement of the signaltonoise ratio in digital holography 77 gram plane ccd plane, and the other from the hologram plane to the image one, as it to is shown in fig. Parallel quasiphaseshifting digital holography request pdf. Holography 1 holography introduction and background the aesthetic appeal and commercial usefulness of holography are both related to the ability of a hologram to store a threedimensional image. Parallel phase shifting digital holographic microscopy ppsdhm figure 1a shows a block diagram of the ppsdhm. Osa multiwavelengthselective phaseshifting digital. Basic principles and experimental verification are described. A phaseshifting digital holography scheme developed to investigate internal defects in artworks is described. Instead, the light wave front information originating from the object is digitally recorded as a hologram, from which a computer.
In digital holography, a reconstruction can be calculated by using the fresnelkirchhoff integral. Fiberoptic displacement sensor to detect the vibration of the thinned usection by fac p. 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. 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. 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. We use phase shifting interferometry selectively extracting wavelength information as a method to obtain multiwavelength object waves separately from wavelengthmultiplexed phase shifted holograms. Singleshot phaseshifting incoherent digital holography iopscience. 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. A phase shifting digital holography scheme developed to investigate internal defects in artworks is described. Calibrated phaseshifting digital holographic microscope. Uncertaintymanaged phaseshifting digital holography joonku hahn1 and hwi kim2, 1school of electronics engineering, kyungpook national university, bukgu sankyukdong, daegu 702701, south korea 2department of electronics and information engineering, college of science and technology, korea university, sejong campus, sejongro 2511, sejong 339700, south korea.
Principles and techniques of digital holographic microscopy myung k. Soraghan, use of fresnelets for phaseshifting digital hologram compression, ieee transactions on image processing 1512, 3804 3811 2006. Pdf correction of phaseshifting error in wavelength scanning. Pdf when structured illumination is used in digital holographic microscopy dhm, each direction of the illumination fringe is required to be shifted. A perpendicularly polarized light beam is emitted from the laser and is split into two beams by a beam splitter. To perform phaseshifting digital holography psdh, several holograms have to be recorded. Optical holography is a method for storage and displaying a threedimensional image of an object. Digital holography technique is the numerical version of conventional holography technique.
Digital holography using a laser pointer and consumer. 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. One beam illuminates the specimen, and then the scattered light from the specimen is collected by a microscope objective. For these reasons, digital and analog holography, along with their many variations i. Development of an optical heterogeneity evaluation system. Incoherent digital holography is a technique to record the complex amplitude distribution of fluorescent, natural light, or another spatially. In digital holography instead of the real object, series of its digital photographs taken from different angles are used.
Phaseshifting errors are introduced in phaseshifted holograms for numerous reasons, such as the nonlinearity of piezoelectric transducers. Moreover, digital sensors have produced a new way to evaluate the object complex amplitude distribution, considering an inline con. It is widely applied in computer reconstruction for the object image, optelectronic reconstruction and the object information measurement, in which the computer reconstruction is the basis of the others. The nondestructive, noncontact, threedimensional evaluation of optical glass has been important to the manufacturing of highprecision optical components.
A reversetransform algorithm is employed to reconstruct the object wave on its original position of unknown distance or the imaging position from the object wave information on the. Berry in 1984 showed that the wavefunction of a quan. In digital holography holograms are recorded by a ccd and image reconstruction is performed by a computer. Phaseshifting digital holography is applied to measure the shapes and positions of rough surfaces from the averaged conjugate product of the reconstructed complex amplitudes, named complex. Twostep phase shifting differentialrecording digital holographic. Phaseshifting inline digital holography on a digital micro. Uncertaintymanaged phaseshifting digital holography. Terahertz digital holography,19,20,21,22,23 has been applied to achieve the simultaneous reconstruction of absorption and phaseshift distributions,21 and a resolution of approximately 0. A thermal deformation measurement system based on calibrated phase shifting digital holography is proposed. Parallel phaseshifting digital holography 2833 is a singleshot phaseshifting technique using an inline system. Parallel phaseshifting digital holographic microscopy. They are recorded by a video camera and transmitted to a computer for realtime numerical reconstruction. As a side effect, the zeroorder term and the twin image can be eliminated in the reconstructed image.
Phaseshifting inline digital holography on a digital. 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. Unlike a photograph, which records the square of the electric eld, a hologram contains both the amplitude and phase information from the image. It has been known that the accuracy of phaseshifting digital holography is limited mainly by the phase tolerance of reference. Computer reconstruction by phaseshifting digital holography. Holograms are generated by combining a coherent reference wave with the wave received from a specimen. Principle of digital holographic microscopy digital holography is based on the classic holographic principle, with the difference that the hologram recording is performed by a digital image sensor, e. The method can reconstruct an arbitrary cross section of a three. Measurement of surface shape and position by phase. Two synchronized ordinary cmos cameras are used in the calibrated phase shifting digital. Because phase is a relative property, construction of a. Holography and speckle in phaseshifting digital holography. Effects of quantization in phaseshifting digital holography. We discuss quantization effects of hologram recording on the quality of reconstructed images in phaseshifting digital 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. The name for the technique that was developed comes from the greek word holos, meaning whole, and gramma, meaning message. Parallel phaseshifting digital holographic microscopy ppsdhm figure 1a shows a block diagram of the ppsdhm. Wave front reconstruction by means of phaseshifting. Yamaguchi and zhang have presented phase shifting digital holography in which four frames of inline holograms and one frame of the intensity pattern of the object wave front were recorded. Improvement of the signaltonoise ratio in digital holography. We propose multiwavelength inline phase shifting digital holography with a monochrome image sensor, single reference arm, and no mechanical scanning. Fiberoptic displacement sensor to detect the vibration of the thinned usection. In phase shifting digital holography an inline setup is employed in the recording to reduce the spatial frequency spectrum of the hologram, and the distribution of complex amplitude on the ccd is directly derived by means of phase shifting of the reference beam and subsequent analysis of hologram patterns to suppress the conjugate image. Image rendering, or reconstruction of object data is performed numerically from digitized interferograms.
A series of phase shifting fringes are generated by computer and outputted by a digital micromirror device dmd. Suppression of the zeroorder and twin images by phaseshifting digital holography allows efficient use of the pixel array 24. Contents 1 introduction 2 2 the development of optical holography 4. Its main limitation that is caused by much lower resolution of ccds than photographic materials has been substantially overcome by phaseshifting digital holography that reduces the spatial frequency of hologram by employing the inline setup and directly evaluates complex amplitude at the ccd plane to eliminate the conjugate and zeroth order. Lightinflight recording by parallel phaseshifting digital. We propose integrated phaseshifting digital holography using statistical approach. With the phase shifting of the reference beam inline holograms for three wavelengths emitted from a hecd laser are recorded simultaneously to derive the. Digital gabor holography, without separate reference. In this paper, we extend gabor and gosss method to include four quadrature phase shifting holograms.
Digital holography is an emerging field of new paradigm in general imaging applications. Mirror with pzt half mirror phase shift half mirror figure 53. Spie applications of digital image processing xxxvi, 20. This film examines the process of holography, types of holograms, and the uses of the hologram for artistic and scientific purposes, as demonstrated by tung h. It has been known that the accuracy of phase shifting digital holography is limited mainly by the phase tolerance of reference.
Digital holography comes in different flavors, such as offaxis fresnel, fourier, image plane, inline, gabor and phaseshifting digital holography, depending on the optical setup. 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. Digital holographic microscopy distinguishes itself from other microscopy methods by not recording the projected image of the object. Threedimensional microscopy with phaseshifting digital holography. Digital holographic interferometry and phaseshifting digital. Full text pdf 17k abstracts references5 the authors present a parallel phaseshifting digital holography as a digital imaging technique for recording and reconstruction of threedimensional object. Digital holograms of a target acquired with a sweptsource laser. Pdf digital holographic microscopy with phaseshiftfree. Nobel prize winner dennis gabor, holographys inventor, saw the film after it was made and said it was the. This approach is based on a gaborlike setup but having two additional elements. Aug 02, 2004 digital holography technique is the numerical version of conventional holography technique. The term hologram is a combination of the greek words holos complete and gram message holography is a process for recording and displaying three dimensional information without lenses therefore holography opens up completely new possibilities in science, engineering, graphics and arts. Digital holographic microscopy dhm is digital holography applied to microscopy. Review of quantitative phasedigital holographic microscopy.
Phase shifting digital holography was also applied to color holography by using a multiline laser and a color ccd shown in fig. Pdf threedimensional microscopy with phaseshifting. A digital phase shifting inline holographic system based on the single coherence beam is developed. I describe its historical development, its basic principles and some examples of its practical application in optical systems. To perform phaseshifting digital holography psdh, several holograms have to. Phaseshifting digital holography has been used for the study of vibrating objects. Due to the red blood cell rbc motion, the light passing through the zebra. Digital holography and 3d imaging dh 21 25 april 20 21 april 20 the fairmont orchid, kohala coast, hawaii united states the digital holography and threedimensional imaging dh topical meeting provides a forum for science, technology, and applications of digital holographic and threedimensional imaging and display methods. 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. Chapter 5 phaseshifting digital holography principles and.
Unlike ordinary photographs, holograms record both phase and amplitude information. Principles and techniques of digital holographic microscopy. The dhm technology generates, in true realtime, high resolution 3d digital images of a sample using the principle of holography. This paper presents the methods for measurement of not only surface shape but also its distance from a charge.
Digital holography tries to display the image as realistic as. 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. The object located at the plane z 0 is coherently illuminated and the optical. It is different from existing methods such as phase shifting. We vary bit depths of phase shifted holograms in both numerical simulation and experiments and then derived the complex amplitude, which is subjected to fresnel transformation for the image reconstruction.
Wave front reconstruction by means of phaseshifting digital. We present twostep phaseshifting differentialrecording digital holographic microscopy tpddh in microscopy for phase imaging of. Thus, phaseshifting digital holography 9,10 removes the distortion incoming from twin images while optimizing the spacebandwidth product of the. Phaseshifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination. Digital holography and 3d imaging dh topical meeting. A significant constraint of digital holography is the pixel count and resolution of the imaging devices. D distribution of complex amplitude without any filtering operation needed in the off. Electro holography aims to be interactive or even realtime and flexible. Yamaguchi, effects of quantization in phaseshifting digital holography, applied optics 4416, 12161225 2005. At that time, scanning devices that could be used for digitizing. 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.
The timeaveraged complex amplitude of fresnel diffracted field due to a vibrating object was obtained by using. Apr 25, 20 digital holography and 3d imaging dh 21 25 april 20 21 april 20 the fairmont orchid, kohala coast, hawaii united states the digital holography and threedimensional imaging dh topical meeting provides a forum for science, technology, and applications of digital holographic and threedimensional imaging and display methods. Nov 05, 2014 we propose integrated phase shifting digital holography using statistical approach. Pdf digital holographic microscopy is a promising method for measuring complex microstructures with high slopes. 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. Retinal blood flow in the optic disc revealed by digital holography duration. Freeviewpoint images captured using phaseshifting synthetic. Javidi, a companding approach for nonuniform quantization of digital holograms of threedimensional objects, optics express 1412, 512954 2006.
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