Presentation on theme: "Diffractive Optical Element"— Presentation transcript:
1Diffractive Optical Element Design Tools andFabrication ProcessKyunghwan Oh,Department of PhysicsYonsei University
2ContentsAvailable DOE design CAD- DECAD- DOE-CAD-W- DiffacMOD- Optis- VirtualLab2. DOE Fabrication Process- Jena Photonics Fabrication Network (JPFN)- Institute of Applied Physics, Fredrich Schiller U.
3Available DOE design CAD More than 6 commercially available CADs- DECAD- DOE-CAD-W- DiffacMOD- Optis- VirtualLabProbably VirtualLab might bethe most recent and and most efficient one.
4Available DOE design CAD DECADFree DownloadLatest Version 2.44, MayLinux OSUsed by Samsung, Sony, ToshibaChalmers University e-beam writter file format only.Other output file formats will be added“DECAD ( Diffractive Element Computer Assisted Design ) is a powerful and versatile software developed by Dr. Olivier MAGNIN for diffractive optics design. DECAD both allows synthesis of diffracting phase functions and accurate simulation of their performances. The simulation engine relies on various selectable propagators (Angular Spectrum, Rayleigh-Sommerfeld, Kirchhoff,... ) that are used by the designer for in-depth analysis of the light diffracted by the DOE aperture.”
5Available DOE design CAD DECADGaussian to Flat-TopAnalytic Phase Function
7Available DOE design CAD DECADSimulation of Diffraction including High OrdersInvestigation of Fabrication Tolerance
8Available DOE design CAD DECADMaster fabricated by e-beam lithography
9Available DOE design CAD DECADExperimental Assessment
10Available DOE design CAD DOE-CAD-WHOLO/OR makes DOE as well as DOE-CAD-WMS-Window basedOne of earliest pioneerCompatible to Optics Tool, Zemax, Oslo, CodeV,along with various outputs“DOE-CAD for windows, masks generation and performance modeling, for diffractive optical elementsDOE-CAD-W is a software package designed to transform phase function specified byuser into the set of mask files for generating multi-level or gray level DOEs.”
12Available DOE design CAD DOE-CAD-WFunctions available in DOE-CAD-WMask files in industrial formats: GDS-II, PostScript, Linework, BitmapMask preview with zoom and cursorMultiplication of DOE into array of elements with 100% full field factorGeneration of off-center part of the DOE-mask.Numerical simulation of focal intensity distributionEstimation of efficiency, accuracy of DOE performance
13Available DOE design CAD DOE-CAD-WFunctional advantages· 2-D nonsymmetrical DOEs supported· Computer simulation of DOE performance· Simulation pictures in standard TIFF image formatProduction management advantages· Mask files placed at any directory on hard disk· Production management support: printing ofproduction form with overview of all DOEspecification, with date, serial number, model, quantity etc.· Inventory of DOE masks inputs.
14Available DOE design CAD DiffacMODA module of Optical Simulation Package,Rsoft Passive Device SuiteDiffractMOD™ is a general design and simulation tool for diffractive optical structures such as diffractive optical elements, subwavelength periodic structures, and photonic bandgap crystals. It is based on the Rigorous Coupled Wave Analysis (RCWA) technique which has been implemented using advanced algorithms including fast Fourier factorization and generalized transmission line formulation.Already a market leader, the tool has extensive applications in a broad range of areas including semiconductor manufacturing and wave optics.
16Available DOE design CAD OptisLSP lab from the University of Strasbourg, France,Gerchberg-Saxton algorithm.Bitmap Image input/outputdemo evaluation version or quotation :“There are a lot of DOE simulation tools, but every feature developed in DOEs simulation tool as been though with tolerancing issues in mind. As a consequence, the final purpose of DOEs simulation tool is to allow every even unskilled user to see the evolution of the reconstructed image quality when changing source or DOE parameters.”
17Available DOE design CAD OptisStep 1 : just define you laser beamStep 2 : define your target with a BMP editor softwareStep 3 : choose DOE parameters you want to build : sampling, number of phase level, nearfield or far field optimizationStep 4 : just press « Start » to see the evolution of your result during the optimization. It willautomatically stop when finishedStep 5 : here is your result : you can see quality, uniformity of the generated DOE, and youobtain a file that represents it: each pixel value (gray level) corresponds to a phase level.This result can be exported as a bitmap or a formatted text file for industrial manufacturing.
19Available DOE design CAD VirtualLabJena, GermanyVersion 3.0 OctoberGeneral Optical Simulation CAD including DOEInstitute of Applied Physics, Fredrich Schiller UniversityFraunhofer Institute of Applied OpticsFabrication service available byJena Photonics Fabrication Network™
20Available DOE design CAD VirtualLabVirtualLab™ - Your BenefitThe electromagnetic field kernel and the generalized spread sheet concept Flexopas™ constitute the fundament of VirtualLab™.Your most essential benefits can be stated in:Light Source ModelsDefinition of System Quality MeasuresAdjustment of Field Propagation TechniquesRapid System InvestigationWave-Optical Design
38Hot Embossing Microfabrication Hot Embossing is a technique of imprinting microstructures on a substrate (polymer) using a master mold (silicon tool).
39Steps in Hot EmbossingHeating Silicon & Polymer above glass transition temperature (Tg).Applying load by pressing the silicon tool on polymer at certain embossing pressure.Cooling the silicon tool and polymer assembly below Tg and de-embossing the tool.Master/Moldfrom Femto-Second LaserHeat the substrateand mold to justabove Tg of thesubstrateApply embossingforce on thesubstrate via themold under vacuumCool thebelow TgDe-embossingof the mold and
40Advantages of Hot Embossing System Cost effective – Easy manufacturability.Time efficient – Fast process.Fabrication of high aspect ratio features.Bio-Compatible surfaces – Polymer substrates used.Disposable – Low cost for volume production.
41Applications of Hot Embossing BioMEMS/Bio-SensorsMicro-Fluidic DevicesMicro-Opticsm-TAS (Micro Total Analysis Systems)
42Hot Embossing v/s Other MEMS Fabrication Processes CharacteristicsLIGASurface Micro-machiningHot EmbossingNumber of layers13-5Minimum feature size5 microns1 micronAspect ratio20N/A10CostHighModerateLowProductivityResidual StressVery Low