Optimal quantization method for unevenphase diffractive optical elements by use of a modified iterative fouriertransform algorithm. Used as multispot beam splitters, in beam shaping, and beam profile modification, such elements offer endless possibilities in different application fields. While standard refractive optical elements such as mirrors and lenses are often bulky, expensive and limited to a specific use, does are generally lightweight, compact, easily replicated, and can modulate complicated wavefronts. Optical microsystems laboratory, department of electrical engineering, koc. In particular, the method uses a nonuniform nu grid and a mapping technique to obtain very accurate spatial derivatives in an ef.
Three methods of designing diffractive optical elements doe are compared. Diffractive optical elements doe holoeye photonics ag. Iterative algorithms for holographic shaping of nondiffracting and. Use features like bookmarks, note taking and highlighting while reading interactive methods for diffractive optical elements computation. Read efficiency optimization approach for twowavelength diffractive optical elements, proceedings of spie on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Noniterative phase hologram computation for low speckle holographic image projection deniz mengu, erdem ulusoy, and hakan urey. An improved iterative algorithm for designing diffractive phase elements for laser beam shaping in free space is presented. Fabrication and application conference paper pdf available in proceedings of spie the international society for optical engineering 9283 april 2014 with 1,245. Doskolovich, iterative methods for diffractive optical elements. Kotlyar and were focused on iterative methods for calculating diffractive optical elements does 414. Mounted versions are well suitable for labbench proofofconcept experiments. Iteractive methods for diffractive optical elements computation. The developed methods allow to increase the energy efficiency of doe, at the same time improving the quality of their work.
Factors affecting convergence in the design of diffractive. By incorporating diffractive optical elements doe in the optical field of. Mcgloin supa, school of physics and astronomy, university of st. The calculation techniques are based on iterative fouriertransform algorithms. This high level monograph for the optics research market explores a large number of novel interactive methods and algorithms for calculating the transmission function of phase diffractive optical elements. Several doe can combine the properties of both diffractive and refractive lenses.
Design and fabrication of diffractive optical elements for. Sep 16, 2016 diffractive optical elements can be realized as ultrathin plates that offer significantly reduced footprint and weight compared to refractive elements. Commonly diffractive optical elements with binary or multilevel steplike profiles are used which are produced by etching technique. Iterative fourier transform algorithm with regularization for. Modified method of increasing of reconstruction quality of diffractive optical elements displayed with lc slm. Diffractive optics as a field has seen a lot of progress in the past decade 1. Pdf three methods of designing diffractive optical elements doe are compared. Wolffsohn,3 and boris chichkov 4 1image processing systems institute branch of the federal scientific research centre crystallography and photonics of russian academy of sciences. Optical tweezer arrays generated by diffractive optical elements can extend the capabilities to manipulate and organize microscopic particles into complex structures, to sort them intelligently and to study collective behavior in manybody systems materials. For example, for focusators the methods allow to reduce the mean square deviation of the. Mar 30, 2012 fabrication of submicronheight relief of threefocal diffractive lenses using twophoton polymerization is studied. Diffractive optical elements and their potential role in high. Multifocal diffractive lens generating several fixed foci at different design wavelengths leonid l. We describe new design methods, based on iterative algorithms, to calculate phaseonly diffractive optical elements able to generate planar and threedimensional arrays of tweezers.
A procedure to calculate a highly quantized, blazed phase structure is presented. Iteractive methods for diffractive optical elements. Computer design of diffractive optics provides an authoritative guide to the principles and applications of computerdesigned diffractive optics. Soifer phase diffractive optical elements calculation using a generalized projections. Pdf backward iterative quantization methods for designs. Combining height and length modulations allows one to increase the diffraction efficiency by more than 10%. Similar to other optical elements with axial symmetry, the diffractive axicon is sensitive to the centration of the doe relative to the optical axis, but it is not sensitive to input beam size and m2 of the laser. However a considerable part of it uses computer generated digital simulations and optimization techniques which utilize the up growing power of modern computation.
Backward iterative quantization methods for designs of multilevel diffractive optical elements article pdf available in optics express. All the methods discussed in this book have been verified by their numerical simulation. This subject is mainly experimental and it is essentially. Spatial light modulator, diffractive optics, multiple laser beams, blazed gratings, iterative fourier transform algorithm. Download it once and read it on your kindle device, pc, phones or tablets.
Improved errorreduction algorithm for designing phase. Analysis and design of diffractive and micro optical systems. Diffractive beamshaping elements at the fabrication limit. The proposed design of the combined diffractiverefractive lenses is promising for the realization of threefocal optical ophthalmological implants with predetermined light intensity. Synthetic phase holograms for autostereoscopic image displays using a modified ifta kyongsik choi, hwi kim, and byoungho lee. The first inclusive book on the cuttingedge field of modern optics and its applicationsfor the first time, all the major aspects of designing planar does are covered in one book, comprised of original methods developed by experts at the russian academy of sciences image processing systems institute. Iteractive methods for diffractive optical elements computation 9780748406340 by soifer, victor a kotlar, v. Moreover, compared to refractive optical elements, does are typically much thinner and lighter, making them an attractive replacement in a number of applications. Opus fau rigorous fourier methods based on numerical. Phase diffractive optical elements calculation using a.
Modified method of increasing of reconstruction quality of diffractive optical elements displayed. Generation of continuous gray levels in threedimensional diffractive optical elements has remained a challenge with the current semiconductor microfabrication method. Diffractive optical elements, does, were designed for applications with lasers and highpower lasers. Iterative methods for diffractive optical elements computation london. We describe new design methods, based on iterative algorithms, to calculate phaseonly diffractive optical elements able to generate. Multifocal diffractive lens generating several fixed foci at. A fouriertransformed synthetic phase hologram for an autostereoscopic image display system is proposed and implemented. Analysis of blazed diffractive optical elements formed. The text includes accounts of wellestablished methods and algorithms for calculating does, but its major contribution is to include current methods and examine the theoretical and practical. The modules are comprised of passive, highefficiency, lowloss diffractive optical elements, combined with fourier transform optics. Synthetic phase holograms for autostereoscopic image. A comparison of the iterative fourier transform method and. Holoeye offers custumized design of diffractive optical elements. Use of twophoton polymerization for continuous graylevel.
This method typically results in optical efficiencies about 7080%. The student will learn how to compute a digital hologram, encode it in a limited diffractive element and optically reconstruct it. Fabrication of submicronheight relief of threefocal diffractive lenses using twophoton polymerization is studied. Pdf comparison of the iterative fourier transform method and. Substantial scattering occurs at the profile steps which also give the tendency to lower damage threshold as compared to intrinsic material values. In this letter, the authors propose and demonstrate the use of the twophoton polymerization method for fabricating threedimensional diffractive optical elements of continuous. Taylor l 1986absorbing boundary condition for difference approximations to the multidimensional wave equation. Hologram generation the holograms are calculated using an iterative fft algorithm, which exploits a numerical method to.
However, due to high periodicity of fluctuations it should be possible to use knowledge of these fluctuations during doe synthesis to minimize negative effect. The areas of applications range from bio technology via printing, material processing, sensing, contactless testing to technical optics and optical metrology. A computational design framework for efficient, fabrication. However, the inherent strong dispersion is an obstacle that limits the use of does in full spectrum imaging, causing.
Efficiency optimization approach for twowavelength. Michael morris the institute of optics university of rocherster rochester, new york 14627. Noniterative phase hologram computation for low speckle. Computergenerated holograms and diffractive optics in scalar diffraction domain 31 light in free space can be described using the kirchhoff diffraction approximation, and the mathematical aspect of light propagation through an optical element reduces to the. A dissertation submitted in partial fulfillment of the requirements.
Design of diffractive lenses for focusing surface plasmons. In the literature, there are several reports on the design and manufacture of thz diffractive. Holoeyes diffractive optical elements does offtheshelf does. Doskolovich, iterative methods for diffractive optical elements computation. Iterative calculation of diffractive optical elements focusing into a threedimensional domain and onto the surface of the body of rotation. To use the fast mean intensity method for calculating. Blockiterative projection methods for parallel computation of solutions to convex feasibility problems. Iterative scalar nonparaxial algorithms for fourier elements.
Diffractive optical element uses a thin micro structure pattern to alter the phase of the. Recent optical solutions with diffractive optical technology. Study of the chromatic properties of harmonic diffractive lens. Since then, the aa algorithm has been adapted to work in the fields of fourier optics by soifer and dr.
The adaptiveadditive algorithm was originally created to reconstruct the spatial frequency phase of light intensity in the study of stellar interferometry. Diffractive optical elements and their potential role in. We demonstrate the use of holographic optical tweezers for trapping particles in air, specifically aerosol droplets. In this letter, the authors propose and demonstrate the use of the twophoton polymerization method for fabricating threedimensional diffractive optical elements of continuous gray levels. Modified method of increasing of reconstruction quality of.
Diffractive optics provide valueadd to laser systems. Methods for computer design of diffractive optical elements is an estimable reference for experts in the aerospace industry, research and development institutes, the automobile industry, as well as students and university professors. Rigorous fourier methods are methods for the rigorous calculation of the scattering of waves at gratings, which are based on fourier expansions of the field and material distribution in the directions of periodicity. Multilevel diffractive optical element manufacture by. Jul 01, 2002 read design and fabrication of diffractive optical elements for optical tweezer arrays by means of ebeam lithography, microelectronic engineering on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Threedimensional vectorial multifocal arrays created by. The breadth of methods for computer design of diffractive optical elements covers doe. A new technique for the analysis of twodimensional diffractive optical elements, by use of the pseudospectral timedomain pstd method, is presented. Experimental results showing the validity of the design approach are presented for an array of eight gaussian spots. A modified iterative fresnel transform algorithm method, for the reconstruction of graylevel quantized stereo images with fast convergence, high diffraction efficiency and large.
The design of diffractive optical elements uses many ideas and concepts from conventional optic designs. Optical implementation of iterative fractional fourier. Algorithms and basics of diffractive optics design. The primary reasons for its success can be attributed to its simplicity in modelling, thingeometry, relatively efficient structures and lowcost manufacturability use of common 3d printable materials 1, 2. Novel diffractive beam splitters with efficiency above 95%. Design rules are described that employ phase retrieval techniques and associated algorithms to determine the necessary profiles of the diffractive optical components. For a given optical path length the phase shift is inversely proportional to the wavelength, so at our operating wavelength of 810 nm the maximum phase shift is reduced to 1. Diffractive optical elements and their potential role in high efficiency illuminators. The design of diffractive optical elements does to generate a desired light intensity distribution has been studied in the realm of diffractive optics. The methods of digital holography 92 enable the synthesis of a hologram which will form the desired wavefront in the first diffraction order, thus reducing the energy efficiency of the optical element.
Stagnation problems are discussed, and methods to overcome them are described. Solving maxwells equations requires a large amount of computing time, which limits the usefulness of fully vectorial methods with respect to design algorithms based on iterative techniques. The iterative fourier transform algorithm ifta is compared to an evolutionary strategy es approach and a combination of both methods. The considered modulation types can be used for the design of general diffractive optical elements by using scalar diffraction theory methods. Iterative methods for diffractive optical elements computation. Applying a mapped pseudospectral timedomain method in. Interactive methods for diffractive optical elements computation kindle edition by leonid doskolovich.
Holographic generation of microtrap arrays for single atoms. The calculation of such optical elements via the methods of raytracing optics 52 disregard the light wave diffraction in free space. Modeling, design and fabrication of diffractive optical elements. Hence, one of the important related issues is the optimal design of does. Iterative fourier transform algorithm with regularization for the optimal design of diffractive optical elements hwi kim, byungchoon yang, and byoungho lee national research laboratory of holography technologies, school of electrical engineering, seoul national university, kwanakgu shinlimdong, seoul 151744, korea. Sculpturing of threedimensional light fields by iterative. Rigorous analysis and design of diffractive optical elements by jianhua jiang a dissertation submitted in partial fulfillment of the requirements for the degree of doctor of philosophy in the optical science and engineering program of the school of graduate studies of the university of alabama in huntsville huntsville, alabama 2000. Holographic optical trapping of aerosol droplets d. Comparison of different freespace propagation methods. We envision that such datadriven design methodologies can apply to other physical sciences domains that require the design of functional elements operating across a wide parameter space. A comparison of the iterative fourier transform method and evolutionary algorithms for the design of diffractive optical elements.
Optical properties of the designed lenses are investigated theoretically and experimentally. The algorithm begins with the gerchbergsaxton approach to obtain a. In monochromatic applications, diffractive microoptical elements are restricted only by the limits of the fabrication technology. Factors affecting convergence in the design of diffractive optics by iterative vectorspace methods henry stark, yongyi yang, and damla gurkan department of electrical and computer engineering, illinois institute of technology, chicago, illinois 60601. Iterative optimization algorithm based on electromagnetic. Diffractive optics are making their way into industry. Lately, significant research has demonstrated the importance of the phase masks presence in various applications such as. The method combines iterative calculation of the hologram phase function with coding of the amplitudephase characteristics of the complex transmission function into phase. Pdf modified method of increasing of reconstruction. An iterative optimization algorithm for designing two dimensions, finite aperture, aperiodic diffractive micro optical elements based on rigorous electromagnetic computation modelthe finitedifference timedomain method has been proposed. Encoded diffractive optics for fullspectrum computational.
Diffractive optical elements does have been studied extensively in optics for decades, but have recently received a lot of renewed interests in the context of computational imaging and computational display because they can drastically reduce the size and weight of devices. Multifocal diffractive lens generating several fixed foci. The text includes accounts of wellestablished methods and algorithms for calculating does, but its major contribution is to include current methods and examine the theoretical and practical aspects of synthesising optical components. The theoretical aspects underpinning diffractive optics are initially explored, including the main equations in diffraction theory and diffractive optical transformations. A novel method is presented to manufacture multilevel diffractive optical elements does in polymer by singlestep.
A comparison of the iterative fourier transform method and evolutionary algorithms for the design of diffractive optical elements philip birch, rupert young, maria farsari, david budgett, john richardson, chris chatwin school of engineering, university of sussex brighton bn1 9qt united kingdom tel. Beside these restrictions, diffractive optical elements. The most accurate description of diffraction can be achieved with fully vectorial computation methods. Methods in optical geometry apply optical elements, including microlens arrays, beam splitters, etalon and diffractive optical elements 4, 5, 812, to. The system uses a phaseonly spatial light modulator and a simple projection lens module. Starikovincreasing reconstruction quality of diffractive optical elements displayed with lc slm. Design and simulation of diffractive optical elements.
Interactive methods for diffractive optical elements. Iterative algorithm for the design of diffractive phase. Iterative calculation of diffractive optical elements. Methods for computer design of diffractive optical elements. Characteristics that are concentrated on are a high diffraction efficiency and a large signaltonoise ratio. Design, analysis, and optimization of diffractive optical. Typical applications for a diffractive axicon include laser corneal surgery, atomic traps, and bessellike beam generation.
An example of this is the socalled harmonic diffractive elements, whereby the diffractive and refractive properties of the lens depends on the phase of bringing the. Modified method of increasing of reconstruction quality of diffractive optical. Implementation of highresolution diffractive optical. Diffractive optical element doe is one of key elements in the complex optical information processing systems that can be used as phase and amplitude filters mainly for synthesizing desired optical field distribution or compensating wavefront aberrations. Within the proposed algorithms to perform the design and optimization of does are the iterative fourier transform algorithms iftas. Multilevel diffractive optical element manufacture by excimer laser. The iterative fourier transform algorithm ifta is compared to an.
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