Lightguides with LED light sources are becoming important components in the application of LCDs for mobile use, because of their thin structures and light weight. Unfortunately, conventional lightguides suffer from poor performance, such as a non-uniform brightness , and this results in poor image and a low efficiency which leads to high power consumption.
{"title":"Vector Radiation Coupling Method for High Efficiency and High Uniformity Lightguide","authors":"M. Shinohara, M. Tei, S. Aoyama, Masashi Takeuchi","doi":"10.1364/domo.1998.dwa.4","DOIUrl":"https://doi.org/10.1364/domo.1998.dwa.4","url":null,"abstract":"Lightguides with LED light sources are becoming important components in the application of LCDs for mobile use, because of their thin structures and light weight. Unfortunately, conventional lightguides suffer from poor performance, such as a non-uniform brightness , and this results in poor image and a low efficiency which leads to high power consumption.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"495 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130989644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bragg diffractions by superimposed transmission phase gratings are important schemes for the realization of optical beam splitters for optical fanout interconnection, neural network implementation, data storage, and parallel optical processing and computing. The theory of optical beam diffractions by superimposed transmission phase gratings have been developed by several authors [1-13]. However, the existing techniques are limited to 2-D diffraction geometry, suffering from numerical problems when the superimposed grating number increases, and/or restricted to small-angle diffractions. For 3-D diffractions by superimposed transmission phase gratings, required for holographic beam splitting applications, there is no simple theoretical model to treat such problem. Complete modal analysis [6,7] already yields complicated results for single-grating diffraction, because the grating vector can have an arbitrary orientation with respect to the plane of incidence. As a consequence the s- and p-polarized field components become coupled inside the grating region and can no longer be treated separately by conventional coupled-wave theory [14]. The coupled 3-D diffraction is much more complicated than the single-grating case. It is, so far, hard for a design engineer to determine suitable grating index combinations prior to device implementation. As a result, superimposed gratings are often recorded through trial and error in hoping on getting a desired energy distributions for splitted beams.
{"title":"Design of holographic optical beam splitters based on thin grating sequential diffraction technique","authors":"Michael R. Wang","doi":"10.1364/domo.1998.jwc.5","DOIUrl":"https://doi.org/10.1364/domo.1998.jwc.5","url":null,"abstract":"Bragg diffractions by superimposed transmission phase gratings are important schemes for the realization of optical beam splitters for optical fanout interconnection, neural network implementation, data storage, and parallel optical processing and computing. The theory of optical beam diffractions by superimposed transmission phase gratings have been developed by several authors [1-13]. However, the existing techniques are limited to 2-D diffraction geometry, suffering from numerical problems when the superimposed grating number increases, and/or restricted to small-angle diffractions. For 3-D diffractions by superimposed transmission phase gratings, required for holographic beam splitting applications, there is no simple theoretical model to treat such problem. Complete modal analysis [6,7] already yields complicated results for single-grating diffraction, because the grating vector can have an arbitrary orientation with respect to the plane of incidence. As a consequence the s- and p-polarized field components become coupled inside the grating region and can no longer be treated separately by conventional coupled-wave theory [14]. The coupled 3-D diffraction is much more complicated than the single-grating case. It is, so far, hard for a design engineer to determine suitable grating index combinations prior to device implementation. As a result, superimposed gratings are often recorded through trial and error in hoping on getting a desired energy distributions for splitted beams.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133554329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1364/domo.1996.jtub.27a
Yang Wang, M. Fiddy, Y. Teng, G. Li, D. Pommet, L. Malley
Holograms recorded in silver halide thin films are transparent when the films are exposed to an inferference pattern of light, developed and bleached. This kind of hologram has been studied by many researchers and is usually called a phase hologram.1,2
{"title":"Measurement and Analysis of Compound Holographic Gratings of Amplitude and Phase","authors":"Yang Wang, M. Fiddy, Y. Teng, G. Li, D. Pommet, L. Malley","doi":"10.1364/domo.1996.jtub.27a","DOIUrl":"https://doi.org/10.1364/domo.1996.jtub.27a","url":null,"abstract":"Holograms recorded in silver halide thin films are transparent when the films are exposed to an inferference pattern of light, developed and bleached. This kind of hologram has been studied by many researchers and is usually called a phase hologram.1,2","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"51 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133651678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the design of diffractive optical elements sophisticated optimization algorithms are required that are capable of finding the optimum structure of the element, described by a set of parameters that define, e.g., the surface profile of one grating period. For binary and multilevel profiles the parameters to be optimized include the profile depth and the positions of the steps or transition points. A wide range of methods exist that are suitable for the solution of this kind of parametric optimization problems, such as direct binary search, conjugate gradient method, steepest-descent method, iterative Fourier-transformation algorithm, simulated annealing, and genetic algorithms.
{"title":"Multilevel diffraction gratings in the resonance domain: rigorous optimization by simulated annealing","authors":"E. Noponen","doi":"10.1364/domo.1998.dmd.2","DOIUrl":"https://doi.org/10.1364/domo.1998.dmd.2","url":null,"abstract":"In the design of diffractive optical elements sophisticated optimization algorithms are required that are capable of finding the optimum structure of the element, described by a set of parameters that define, e.g., the surface profile of one grating period. For binary and multilevel profiles the parameters to be optimized include the profile depth and the positions of the steps or transition points. A wide range of methods exist that are suitable for the solution of this kind of parametric optimization problems, such as direct binary search, conjugate gradient method, steepest-descent method, iterative Fourier-transformation algorithm, simulated annealing, and genetic algorithms.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132569295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Surface-relief diffractive optical elements (DOEs) have a wide range of applications in present-day optical systems. DOEs have been used for the achromatization, color-correction, and athermalization of imaging systems. Diffractive phase plates are used as fanout gratings in optical interconnect and laser machining applications. Phase plates are also prevalent in display and alignment applications whereby they are used to generate arrows, company logos, and grids and lines, respectively. The ability to design and fabricate high-quality, precision, surface-relief, DOE masters requires a high level of intellectual property in addition to sophisticated manufacturing infrastructure. However, once a high-quality DOE is produced, it is an easier task to produce polymer replicas of the surface using technologies such as cast-and-cure, embossing, and injection molding.[1] The technology to perform high-quality replicas of DOE surfaces is becoming more prevalent globally. As the volume of surface-relief DOEs inserted into the marketplace increases, one must consider measures to deter unauthorized reproductions of one’s intellectual property. Counterfeiting is a $50 billion dollar a year business,[2] and although most of the items counterfeited include computer hardware and software, clothing, and perfume, DOEs, as their market-presence increases, will attract counterfeiters.
{"title":"Counterfeit-Deterrents for Surface-Relief Diffractive Optical Elements","authors":"D. Raguin, R. Mcguire, G. Gretton","doi":"10.1364/domo.1998.dwb.2","DOIUrl":"https://doi.org/10.1364/domo.1998.dwb.2","url":null,"abstract":"Surface-relief diffractive optical elements (DOEs) have a wide range of applications in present-day optical systems. DOEs have been used for the achromatization, color-correction, and athermalization of imaging systems. Diffractive phase plates are used as fanout gratings in optical interconnect and laser machining applications. Phase plates are also prevalent in display and alignment applications whereby they are used to generate arrows, company logos, and grids and lines, respectively. The ability to design and fabricate high-quality, precision, surface-relief, DOE masters requires a high level of intellectual property in addition to sophisticated manufacturing infrastructure. However, once a high-quality DOE is produced, it is an easier task to produce polymer replicas of the surface using technologies such as cast-and-cure, embossing, and injection molding.[1] The technology to perform high-quality replicas of DOE surfaces is becoming more prevalent globally. As the volume of surface-relief DOEs inserted into the marketplace increases, one must consider measures to deter unauthorized reproductions of one’s intellectual property. Counterfeiting is a $50 billion dollar a year business,[2] and although most of the items counterfeited include computer hardware and software, clothing, and perfume, DOEs, as their market-presence increases, will attract counterfeiters.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127648183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guided-mode resonance (GMR) effects are observed in dielectric and semiconductor thin-film structures comprising diffractive and waveguide layers1,2. High-efficiency resonances are realizable under zero-order conditions imposed by a diffractive element with suitably high spatial frequency such that all higher-order diffracted waves are evanescent. For parametric conditions such that one of these evanescent waves couples to a (leaky) waveguide mode, a resonance occurs with associated strong power exchange between the propagating zero-order waves. This resonance coupling effect is typically represented as spectral (with constant angle of incidence) or angular (with constant wavelength) variation of the diffraction efficiency of the transmitted and reflected waves. Theoretical and experimental studies1–10 have illustrated the feasibility of utilizing this basic effect for numerous applications11.
{"title":"Guided-mode resonant filters incorporating the Brewster effect","authors":"R. Magnusson, D. Shin, Z. Liu","doi":"10.1364/domo.1998.dmb.2","DOIUrl":"https://doi.org/10.1364/domo.1998.dmb.2","url":null,"abstract":"Guided-mode resonance (GMR) effects are observed in dielectric and semiconductor thin-film structures comprising diffractive and waveguide layers1,2. High-efficiency resonances are realizable under zero-order conditions imposed by a diffractive element with suitably high spatial frequency such that all higher-order diffracted waves are evanescent. For parametric conditions such that one of these evanescent waves couples to a (leaky) waveguide mode, a resonance occurs with associated strong power exchange between the propagating zero-order waves. This resonance coupling effect is typically represented as spectral (with constant angle of incidence) or angular (with constant wavelength) variation of the diffraction efficiency of the transmitted and reflected waves. Theoretical and experimental studies1–10 have illustrated the feasibility of utilizing this basic effect for numerous applications11.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131266993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1364/domo.1996.jtub.26
G. Wenqi, Tan Suqing, Zhou Jin
Usually in reconstruction of Fourier computer-generated hologram[FCGH] the lens is necessary to make imaging at finite distance instead of imaging at infinite originally. The reconstructed images are mutual inverted ( one upright image,another inverted image) both appear in a same plane. Whether the imaging lens in reconstruction FCGH will be able to omit? Whether two reconstructed images will be able to separate in spatial? Whether two images have an identical direction and different shape in the same plane? It is the motivation for us to do this study. Through theoretic analysis and experimental reconstruction these assume can be realized essentially.
{"title":"Computer-generated hologram for reconstruction of unusual mode image","authors":"G. Wenqi, Tan Suqing, Zhou Jin","doi":"10.1364/domo.1996.jtub.26","DOIUrl":"https://doi.org/10.1364/domo.1996.jtub.26","url":null,"abstract":"Usually in reconstruction of Fourier computer-generated hologram[FCGH] the lens is necessary to make imaging at finite distance instead of imaging at infinite originally. The reconstructed images are mutual inverted ( one upright image,another inverted image) both appear in a same plane. Whether the imaging lens in reconstruction FCGH will be able to omit? Whether two reconstructed images will be able to separate in spatial? Whether two images have an identical direction and different shape in the same plane? It is the motivation for us to do this study. Through theoretic analysis and experimental reconstruction these assume can be realized essentially.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129495636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Numerous tasks of laser pointing, visual adjustment, targeting and laser radar require shaping of laser diode beam into the line contour patterns. The examples of the line patterns are straight-line segment, cross, contour of rectangle, system of points. One more task is to circularize the elliptical beam that is typical for laser diodes even after passing through standard collimators. The traditional approach is either to use cylindrical lenses1 or to apply computer-generated phase holograms reconstructing the system of points2. The usual problem in computer-generated holograms is the dot-type structure of the image, limited possibilities to achieve uniform intensity distribution along lines. Patterns containing several lines can be formed by faceted diffractive optical elements (DOEs), which use some part of clear aperture for line segment generation. However splitting the aperture adds problems in line uniformity, width, interference between lines. Other way is to use multi-channel DOEs3 utilizing several diffraction orders of DOE at once. We propose a special way to generate symmetrical patterns based on the full use of symmetrical diffraction orders of binary diffraction grating. Full cycle of design, computer simulation, fabrication and experimental investigation of DOEs for laser diodes is described in this report.
{"title":"Two-level binary diffractive optical elements for symmetric line-patterns generation from laser diodes","authors":"M. Golub","doi":"10.1364/domo.1998.dmd.5","DOIUrl":"https://doi.org/10.1364/domo.1998.dmd.5","url":null,"abstract":"Numerous tasks of laser pointing, visual adjustment, targeting and laser radar require shaping of laser diode beam into the line contour patterns. The examples of the line patterns are straight-line segment, cross, contour of rectangle, system of points. One more task is to circularize the elliptical beam that is typical for laser diodes even after passing through standard collimators. The traditional approach is either to use cylindrical lenses1 or to apply computer-generated phase holograms reconstructing the system of points2. The usual problem in computer-generated holograms is the dot-type structure of the image, limited possibilities to achieve uniform intensity distribution along lines. Patterns containing several lines can be formed by faceted diffractive optical elements (DOEs), which use some part of clear aperture for line segment generation. However splitting the aperture adds problems in line uniformity, width, interference between lines. Other way is to use multi-channel DOEs3 utilizing several diffraction orders of DOE at once. We propose a special way to generate symmetrical patterns based on the full use of symmetrical diffraction orders of binary diffraction grating. Full cycle of design, computer simulation, fabrication and experimental investigation of DOEs for laser diodes is described in this report.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127466525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1364/domo.1998.dtud.6
H. Bartelt, T. Glaser, S. Schroeter
Grating structures with a grating period in the range of the illumination wavelength differ in their diffraction properties considerably from conventional diffraction structures. In this case diffraction properties are sensitive in a complex manner to illumination direction, structure thickness, illumination wavelength or polarization. For modeling of the diffraction properties rigorous solutions of the wave have to be used [1]. Specific examples of the properties of such gratings include highly efficient single order gratings or polarization dependent beam splitting structures [2]. Although theoretical modeling of such gratings is known for a long time, practical realization of such gratings was limited until recently by the structuring technology. After first investigations based on an interferometric technique now also more flexible techniques based on direct e-beam writing in the submicrometer range become available [3]. In the following we want to describe at first results for the design of an efficient single order binary phase grating structure. Then the combination of two single order gratings for achieving beam switching properties with small mechanical shifts in the sub micrometer range will be discussed.
{"title":"Binary high-efficiency single order gratings for beam switching","authors":"H. Bartelt, T. Glaser, S. Schroeter","doi":"10.1364/domo.1998.dtud.6","DOIUrl":"https://doi.org/10.1364/domo.1998.dtud.6","url":null,"abstract":"Grating structures with a grating period in the range of the illumination wavelength differ in their diffraction properties considerably from conventional diffraction structures. In this case diffraction properties are sensitive in a complex manner to illumination direction, structure thickness, illumination wavelength or polarization. For modeling of the diffraction properties rigorous solutions of the wave have to be used [1]. Specific examples of the properties of such gratings include highly efficient single order gratings or polarization dependent beam splitting structures [2]. Although theoretical modeling of such gratings is known for a long time, practical realization of such gratings was limited until recently by the structuring technology. After first investigations based on an interferometric technique now also more flexible techniques based on direct e-beam writing in the submicrometer range become available [3]. In the following we want to describe at first results for the design of an efficient single order binary phase grating structure. Then the combination of two single order gratings for achieving beam switching properties with small mechanical shifts in the sub micrometer range will be discussed.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127949350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1364/domo.1998.dtud.1a
L. Cai, Chun-fei Li, Jianhua Zhao, Hua-Kuang Liu
We have analyzed the transmitted spectra of optical elements including the phase gratings and Fabry-Perot (FP) and found design parameters of these elements for the elimination/reduction of on-axis transmission of broadband of visible light. In this paper, we will present a detailed theoretical analysis on the design and performance of the optical elements that will greatly reduce the transmittance of the beam in its original path of propagation. We will give the numerical computation results derived from the formula showing the spectral dependence of the direct intensity transmittance for different optical elements.
{"title":"Optical Elements for Elimination of On-Axis Visible Transmission","authors":"L. Cai, Chun-fei Li, Jianhua Zhao, Hua-Kuang Liu","doi":"10.1364/domo.1998.dtud.1a","DOIUrl":"https://doi.org/10.1364/domo.1998.dtud.1a","url":null,"abstract":"We have analyzed the transmitted spectra of optical elements including the phase gratings and Fabry-Perot (FP) and found design parameters of these elements for the elimination/reduction of on-axis transmission of broadband of visible light. In this paper, we will present a detailed theoretical analysis on the design and performance of the optical elements that will greatly reduce the transmittance of the beam in its original path of propagation. We will give the numerical computation results derived from the formula showing the spectral dependence of the direct intensity transmittance for different optical elements.","PeriodicalId":301804,"journal":{"name":"Diffractive Optics and Micro-Optics","volume":"94 10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127982954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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