Measurement of surface shape and position by phaseshifting. We applied phase shifting digital holography to microscopy by deriving the complex amplitude of light scattered from microscopic threedimensional objects through a microscope objective by video camera recording, phase shifting analysis, and computer reconstruction. Digital holography can be adapted appropriately for. The compression techniques that have been proposed to date aim at compressing the complex wavefront at the plane of the recording camera. The measurement of the intensity map of the object light can be omitted in threeexposure qpsh. We conduct both numerical simulation and preliminary experiment. One beam illuminates the specimen, and then the scattered light from the specimen is collected by a microscope objective. 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.
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. 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. To explain this, we plot the amplitude and phase uncertainties for thecombinatorialpairsofi1,i2,andi3 onthesamegraph in figs. Parallel phase shift digital holography ppsdh is particularly suitable for measuring moving objects. Digital holography fourier optics and computational imaging. Speckle noise suppression in measurement by phaseshifting. In phaseshifting 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 phaseshifting of the reference beam and subsequent analysis of hologram patterns to suppress the conjugate image. Spectral phase shifting interferometry with a partially coherent light source has been proved to be superior to the alternatives because of its fast and speckle free measurement capability 11. Parallel phaseshifting digital holographic microscopy. It considers three different approaches such as off. Parallel phase shifting digital holographic microscopy ppsdhm figure 1a shows a block diagram of the ppsdhm. An acoustooptic tunable filter aotf is adopted to implement wavelength scanning. One holographic setup method that can reduce the noises mostly is a wider viewing angle from conventional digital hologram using an offaxis configuration, called phaseshifting digital holography.
Lightinflight recording by parallel phaseshifting digital. 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. We applied phaseshifting digital holography to microscopy by deriving the complex amplitude of light scattered from microscopic threedimensional objects through a microscope objective by video camera recording, phaseshifting analysis, and computer reconstruction. Measurement of surface shape and position by phase. Twosteponly quadrature phaseshifting digital holography. A schematic of bimodal incoherent digital holography for both of 3d and qidof imaging.
Pdf when structured illumination is used in digital holographic microscopy dhm, each direction of the illumination fringe is required to be shifted. It derives the phase of the averaged conjugate product of complex amplitudes before and after wavelength change or object deformation, corresponding to the complex coherence factor, and is. 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. The optical phase of the reference beam is shifted. Phaseshifting digital holography with compensation of. Digital holography dh 1016 is a technique in which a digital hologram that contains an object wavefront is recorded, and both 3d and quantitative phase images of an object are reconstructed using a computer. Pdf threedimensional microscopy with phaseshifting. Techniques of digital holography are improved in order to obtain high. Suppression of the zeroorder and twin images by phaseshifting digital holography allows efficient use of the pixel array 24. Dec 15, 2000 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. It is free from tedious photographic processing and delivers threedimensional distributions. 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.
The improved reconstruction quality that phaseshifting interferometry digital holography offers compared to conventional digital holography comes with an extra computation cost, increased recording complexity and additional data storage demands. Phaseshifting imageplane digital holography is considered as a widelyused measuring method for observation of microscale phase objects and for nondestructive testing of phase morphology. Feb 20, 2002 phase shifting digital holography with compensation of aberrations a phase shifting machzehnder interferometer is used for recording four quadrature phase shifted offaxis holograms. Various temporal or spatial phase shifting methods have been used to realize the recording of multiple phase shifting interferograms 1115. This paper presents the methods for measurement of not only surface shape but also its distance from a chargecoupled device ccd by using phaseshifting digital holography 8. In phaseshifting method, it is often used four steps of phaseshifting for one cycle. Digital gabor holography, without separate reference. Chapter 5 phaseshifting digital holography principles and. 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 this technique, a monochrome image sensor records wavelengthmultiplexed, phase shifted, and incoherent holograms, and a phase shifting interferometry technique selectively extracts object waves at multiple wavelengths from the several recorded holograms. This method generates images of objects, but the image quality is diminished because they contain abundant speckle noise. Effect of phaseshifting error on deformation evaluation. A perpendicularly polarized light beam is emitted from the laser and is split into two beams by a beam splitter.
In conventional method, to measure the displacement of an object by an interferometer, the phase of a reference beam should be shifted by every. Twostep phase shifting differentialrecording digital holographic. Phase shifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination. Correction of phaseshifting error in wavelength scanning. The basic principle of this technique and its experimental verification are described. Digital holography comes in different flavors, such as offaxis fresnel, fourier, image plane, inline, gabor and phase shifting digital holography, depending on the optical setup. Apr 21, 2006 the improved reconstruction quality that phase shifting interferometry digital holography offers compared to conventional digital holography comes with an extra computation cost, increased recording complexity and additional data storage demands. This spatial division phaseshifting method is referred as a parallel phaseshifting 37, and widely applied in various digital holography systems. Digital holography offers a means of measuring optical phase data and typically delivers threedimensional surface or optical thickness images.
Digital holography fourier optics and computational. In transmission, the phase image reveals the phase shift induced by a transparent specimen, which can be interpreted in terms of many underlying biological processes. This digital approach to holography allows the application of computer based procedures at a level unreached in videomicroscopy. One holographic setup method that can reduce the noises mostly is a wider viewing angle from conventional digital hologram using an offaxis configuration, called phase shifting digital holography. The technique implements four kinds of phase shifting at a time using a phase shifting array device located in the reference beam. By the ppscdhm, instantaneous information of not only the 3d structure of specimens but also the spectral image can be simultaneously acquired with a singleshot exposure. We propose parallel quasiphaseshifting digital holography as a technique capable of noiseless instantaneous measurement of threedimensional objects. Parallel phaseshifting digital holographic microscopy ppsdhm figure 1a shows a block diagram of the ppsdhm.
This spatial division phase shifting method is referred as a parallel phase shifting 37, and widely applied in various digital holography systems. Fast method of recovering referencewave intensity in two. Uncertaintymanaged phaseshifting digital holography. By digital holography the intensity and the phase of electromagnetic wave. Pdf geometric phase shifting digital holography researchgate. Parallel phaseshifting color digital holographic microscopy. Based on phaseshifting interferometry 31, 32, only the objectwave information is extracted with multiple phaseshifted holograms. Mirror with pzt half mirror phase shift half mirror figure 53. Pdf a new phase shifting digital holographic technique using a. A new algorithm for fringe phase analysis is proposed for shape and deformation measurement of diffusely reflecting surfaces by digital holography. A couple of years later, burckhardt and enloe proposed threestep phaseshifting holography when they investi. Compression of phaseshifting digital holography interference.
The elliptical vortex sieve is a kind of amplitudeonly diffractive lenses which can be used for focusing and imaging from coherent xrays to terahertz regime. Building up from the basic principles of optics, this book describes key techniques in digital holography, such as phase shifting holography, lowcoherence. Threedimensional microscopy with phaseshifting digital. Owing to the need for multiple phaseshift holograms to be recorded and the requirement for phase stability among the different phase shifts in order to obtain good quality image reconstruction in three and fourstep phaseshifting holography, quadrature phaseshifting techniques found advocates in recent years 812. Threedimensional microscopy with phase shifting digital holography. Building up from the basic principles of optics, this book describes key techniques in digital holography, such as phaseshifting holography, lowcoherence. 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 other one is phase shifting digital holography, which can precisely retrieval the phase information from more than one interferograms. 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. Quantitative phase microscopy qpm has recently emerged as a new powerful quantitative imaging technique well suited to noninvasively explore a transparent specimen with a nanometric axial sensitivity. After extraction, a holographic image of an object is obtained. In addition, the phaseshifting errors may cumulate or not according to different phaseshifting techniques, and both cases are considered in this paper.
We vary bit depths of phase shifted holograms in both numerical simulation and experiments and then derived the complex. We propose parallel phaseshifting color digital holographic microscopy ppscdhm which is capable of both color imaging and threedimensional 3d motion measurement by using spacedivision multiplexing technique. Quadrature phaseshifting holography qpsh, also called twostep phaseshifting holography, was. Free viewpoint 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. Highresolution quantitative phasecontrast microscopy by. Comparison of two, three, and fourexposure quadrature. A significant constraint of digital holography is the pixel count and resolution of the imaging devices. Full size image in contrast, the other beam copy propagates a. Setup for microscopy using phaseshifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5. Nobel prize winner dennis gabor, holographys inventor, saw the film after it was made and said it was the. Pdf digital holographic microscopy with phaseshiftfree. The amplitudeonly vortex lens is a kind of diffractive optical elements does which can be used for focusing and imaging in a wide spectral region, such as coherent x. Introduction to modern digital holography pdf book manual.
Twosteponly quadrature phaseshifting digital holography faculty. Parallel phaseshift digital holography ppsdh is particularly suitable for measuring moving objects. Phase shifting imageplane digital holography is considered as a widelyused measuring method for observation of microscale phase objects and for nondestructive testing of phase morphology. Effects of quantization in phaseshifting digital holography. Phase shifting digital holographypsdh has proved to. Figure 1b shows multiple holograms with different phases sequentially recorded with a phase modulator, such as a piezodriven mirror, an slm, an acoustooptic modulator, or an electrooptic modulator.
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. Zhang, phaseshifting digital holography, optics letters 22, 12681270 1997. We propose multiwavelengthmultiplexed phase shifting incoherent color digital holography. Phaseshifting digital holography also directly provides the 3d distribution of complex amplitude without any. Phaseshifting method with unknown intervals in phase. In digital holography holograms are recorded by a ccd and image reconstruction is performed by a computer. It is well known that one cannot image directly through a nonlinear medium, as intensitydependent phase changes distort signals as they propagate. Highresolution quantitative phase contrast microscopy by digital holography christopher j. They are recorded by a video camera and transmitted to a computer for realtime numerical reconstruction. Digital holography and its multidimensional imaging. Setup for microscopy using phase shifting digital holography without imaging lens onion peels z 17mm, zq itmm, magnification m5. Digital holography refers to the acquisition and processing of holograms with a digital sensor array, typically a ccd camera or a similar device.
Highresolution quantitative phasecontrast microscopy by digital holography christopher j. Singleshot phaseshifting incoherent digital holography iopscience. Basic principles and experimental verification are described. We propose parallel phase shifting color digital holographic microscopy ppscdhm which is capable of both color imaging and threedimensional 3d motion measurement by using spacedivision multiplexing technique. Phaseshifting digital holography 151 beam is frequency shifted and an object is scanned by an xy stage under focused illumination. Suppression algorithm of speckle noise for parallel phase. May 15, 2020 introduction to modern digital holography with matlab get up to speed with digital holography with this concise and straightforward introduction to modern techniques and conventions. Digital holography is the best tool for measuring object information data.
Bimodal incoherent digital holography for both three. Phase shifting digital holography psdh is considered as a promising imaging technique with wide application in optical storage, topography measurement and defect detection. This method requires no mechanical movement and provides a flexible display and quantitative evaluation of the reconstructed images. Parallel quasiphaseshifting digital holography request pdf. Free viewpoint 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. Suppression of the zeroorder and twin images by phase shifting digital holography allows efficient use of the pixel array 24. We discuss quantization effects of hologram recording on the quality of reconstructed images in phaseshifting digital holography. Introduction to modern digital holography pdf book.
To perform phaseshifting digital holography psdh, several holograms have to be recorded, each with the phase of the reference wave shifted to different states. Mar 22, 2009 it is well known that one cannot image directly through a nonlinear medium, as intensitydependent phase changes distort signals as they propagate. Principles and techniques of digital holographic microscopy. Computer simulation and experimental results have been performed to verify the effectiveness and feasibility of our proposed method.
Displacement measurement can be performed with high accuracy using phaseshifting method. Image rendering, or reconstruction of object data is performed numerically from digitized interferograms. Freeviewpoint images captured using phaseshifting synthetic. This method requires no mechanical movement and provides a flexible display and quantitative evaluation of the reconstructed. Review of quantitative phasedigital holographic microscopy. Daniel claus, daciana iliescu, and peter bryanstoncross, quantitative spacebandwidth product analysis in digital holography applied optics,vol. Phaseshifting digital holography psdh is considered as a promising imaging technique with wide application in optical storage, topography measurement and defect detection. Imaging through nonlinear media using digital holography. Calibrated phaseshifting digital holographic microscope.
Phaseshifting imageplane digital holography with elliptical. Introduction to modern digital holography with matlab get up to speed with digital holography with this concise and straightforward introduction to modern techniques and conventions. For hologram recording a conventional holographic setup can be used, as long as a phaseshifting element is included in the optical path of the reference beam see fig. In standard four exposure quadrature phaseshifting holography qpsh, two holograms and two intensity maps are acquired for zeroorder free and twinimage free reconstruction. It is free from tedious photographic processing and delivers threedimensional distributions of both amplitude and phase quantitatively. Digital holography generally offers more flexibility than conventional holographic interferometry and speckle interferometry because of its simple setup and easy.
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