Development of a new multi-wavelength confocal surface profilometer for in-situ automatic optical inspection (AOI)
|
|
- Phebe James
- 5 years ago
- Views:
Transcription
1 Development of a new multi-wavelength confocal surface profilometer for in-situ automatic optical inspection (AOI) Liang-Chia Chen 1#, Chao-Nan Chen 1 and Yi-Wei Chang 1 1. Institute of Automation Technology, National Taipei University of Technology. No.1, Sec. 3, Chung-Hsiao East Road, Taipei, Taiwan 1061 # Corresponding Author / lcchen@ntut.edu.tw, TEL: , FAX: KEYWORDS : Automatic optical inspection (AOI),confocal measurement, chromatic multi-wavelength, three-dimensional measurement An in-situ 3-D surface profilometer for inspecting micro surface profiles with a long vertical range and high resolution was successfully developed by using innovative slit-scan multi-wavelength confocal surface profilometry. In conventional confocal microscopy, vertical scanning of a tested surface by either stage depth movement or shifting of optical objectives is of time consuming, thus making unacceptable measurement efficiency for in-situ inspection. To overcome this, in the research, a multi-wavelength confocal system employing a broad band light source in combination with a chromatic dispersion objective was developed to generate an accurate wavelength-to-depth conversion for in-situ 3-D profile measurement. The specially designed objective is capable of modulating a broadband light to produce axial chromatic dispersion with respect to a corresponding series of axial focusing depths along the vertical-axis and then to obtain the corresponding reflected light spectrum from the object s surface. By designing the objective, the depth measurement range can be ranged between few to several hundred micrometers and the depth measurement resolution can theoretically reach to 0.03% of the overall detection range. From the experimental test, it was found that the maximum measurement error and repeatability can be controlled well within 0.099% of the overall measurement range and 52 nm in one standard deviation, respectively. By integrating a high-speed image acquisition unit, the measurement efficiency can be further enhanced for in-situ automatic optical inspection (AOI). Manuscript received: July 15, 2009 / Accepted: August 15, INTRODUCTION Confocal microscopy has become a powerful measurement method due to its unique optical sectioning capability. The confocal measurement utilizes the geometrical matching of two conjugate focal points corresponding to both the object surface and the point detector defined by a pinhole [1,2]. Conventional laser confocal measurement has been widely used to reconstruct 3-D surface contours in biomedical application. Laser light has its advantages in overcoming large variation of surface reflectivity while other methods may suffer from the limitation severely. However, this kind of the method has also been restricted by its inefficient scanning rate and in general has been difficult to achieve in-situ surface profilometry. In recent years, a digital micromirror device (DMD) can be deployed as an array of pinholes for confocal lateral scanning. The DMD used as a spatial light modulator has a number of independently controlled micro mirrors for generating defined spatial fringe modulations of light field as structured light in modern 3-D profilometry [3]. To increase scanning efficiency, several methods have also been developed to fasten profile measurement. Most importantly, the Nipkow disk, as a way to transmit images electrically using a pair of spinning metal disks or the use of a diffractive lens illuminated with a tunable light source, has been utilized to improve confocal scanning speed [4]. Using micro-lens arrays, it can be employed to obtain full-field 3-D information by vertical scanning [5]. A non-moving agile scanning confocal microscope system employing variable-focal-length (VFL) micro-lenses also provided a way to axially scan the foci across a sample [6]. Meanwhile, a method and apparatus using multiple imaging paths with respect to different object viewing angles was developed to measure object height and volume using a combination of optical means and image processing techniques [7]. Another potential technique is the chromatic confocal microscopy, which takes the advantage of light for avoiding vertical scanning completely. A chromatic confocal microscope generally equips with a white-light source in combination with a diffractive lens as well wavelength-to-depth coding for profile measurement of a three-dimensional surface [8]. Nevertheless, none of the existing chromatic methods has so far explored the possibility of developing a compact reflective-lens objective for achieving axial light dispersion required for depth evaluation. Therefore, the research developed a chromatic confocal profilometer by designing a reflective-lens objective and line-slit confocal optical configuration for achieving line scanning surface profilometry. The chromatic objective was designed by using optimizing light refractive property with different materials of optical lenses and various optical configurations. A system calibration was also implemented to obtain accurate mapping between light wavelength and depth. The details of the system design and measurement principle are provided in the following sessions.
2 2. SLIT-SCAN CHROMATIC CONFOCAL SYSTEM SETUP AND PRINCIPLE 2.1 Traditional confocal and chromatic confocal principle Traditional confocal principle is a widely used method to reconstruct 3-D volumetric structures of a tested object. When the object locates on the focal plane of a confocal layout, the reflected light from the object s surface can pass thought a spatially filtering pinhole and reach to the detector with a maximum light intensity. However, when it is out of the focal plane, the detector will only obtain smaller amount of light and the detected light is attenuated significantly, as shown in figure 1. A vertical scanning can be used to establish a depth response curve of the light intensity, which primarily depends on the light wavelength and the numerical aperture of the objective. The light intensity detected in the above conjugative optical configuration can be shown in Eq. (1) [2]. Photo detector Illuminating aperture Pinhole respect to the light wavelength, an accurate mapping curve (shown in figure 4) between the light wavelength and the detected profile depth can be established by referencing a vertical-scanning reference mirror with a calibrated laser interferometer. With the knowledge of the detected wavelength with respect to its corresponding focal depth, the calibrated mapping function can be employed to detect height information without in-situ vertical scanning. White light source Spectrometer Conjugate spatial filter Spatial filter Object surface Beam splitter λ min λ m λmax Spectral Image λ min λ m λ max Wavelength Point light source Beam splitter Fig. 3 Schematic diagram of the developed chromatic confocal microscope. In-focus rays Out-of-focus rays Focal plane Sample Z-axis distance Peak Depth (μm) Least-squares fit Focal length Fig. 1 Traditional confocal microscope 0 sin( u / 2) ( u) ( / 2) u 2 I (1) where 8 2 is the normalized axial coordinate; u Z sin 2 λ is the wave-length of the light source; z is the vertical distance; and α is the half angle of the field of view. The traditional confocal method described above definitely needs a vertical scanning operation for determining its focus peak. To avoid this time-consuming process, the chromatic confocal method employs chromatic light dispersion along the depth axis to obtain the mapping relationship between profile depth and light wavelength. In this research, a chromatic optical objective has been designed and fabricated to focus the incident white light onto a series of focal distances with respect to the corresponding wavelength, shown in figure 2. White light source λ1λ 2 λm λn Fig. 2 Illustration of axial chromatic light dispersion generated by the developed chromatic optical objective. The optical system and its spectrum intensity signal of the developed chromatic confocal system are illustrated in Figure 3. Using a spectrometer to analysis the received intensity response with Wavelength (nm) Fig. 4 Calibrated mapping curve between light wavelength and profile depth. 2.2 Slit-scan Chromatic confocal microscope and measurement Principle Traditional chromatic confocal profilometers are in general a point-type profile scanner, which is not efficient for in-situ inspection. To achieve a better solution, a slit-scan chromatic confocal profilometer was developed here to perform continuous line-scan profile measurement. In general, the slit-scan has slightly less measurement resolution than the point scan; however, it has a larger field of view (FOV) and a higher measurement speed. The optical configuration of the developed slit-scan chromatic confocal system and its hardware setup are illustrated in Figure 5 and Figure 6, respectively. In the system, a white light supplied by a Xenon arc lamp is first coupled into an optical fiber and then focused by a cylinder lens to form a projected line-shape light source. It is then forwarded through a line aperture for refining its light shape and uniformity and further passing through a beam-splitter for redirecting light into the chromatic objective. Being chromatically dispersed by the objective, the incident light is then projected onto the tested object surface. Following the light being reflected back from the object s surface, it is then transmitted through the coaxial optical structure having a conjugate slit aperture and to be further received by a line spectrometer. The slit aperture is employed to filter out defocused light and differentiate focused light from other unfocused beams for generating a good depth detection resolution. The detected spectrum information includes the light wavelength, light intensity and
3 horizontal position. Figure 7 shows an example of the spectrum image of a step-height surface. By using the mapping function established in session 2.1, the cross-section surface profile (illustrated in Figure 7) of the measured step-height surface can be obtained. A full-field 3-D map can be further achieved by moving a translation stage along the scanning axis. Computer Line-spectrometer Cylindrical Lens White-Light Source 100W Xe Lamp Input slit aperture Translation stage Conjugate slit aperture Sample Beam splitters Wavelength Peak Fig. 5 Schematic diagram of the developed slit-scan chromatic confocal surface profilometer. Fig. 7 Measurement results of a step-height surface by using the developed slit-scan chromatic confocal system: the detected spectrum image; and the reconstructed crosssection profile. 2.3 Design of the chromatic objective To obtain a desired specification of the axial chromatic light dispersion with a specific measurement depth range and minimal image aberration, an optical lens design and optimization using commercial optics software was implemented by minimizing potential image aberrations and lens fabrication costs. The light disperse range can be accurately controlled by careful selection of various material properties of optical lenses with geometric parameters, the focal distance and the working distance. In a design example of a 20x chromatic objective by using biconvex lenses having various positive and negative meniscuses, an optical layout can be designed with its ray tracing shown in Figure 8. In this case, a light spectral bandwidth range between 400 nm and 700 nm was chosen for its optical simulation. With an optical simulation and optimization, the optical design can be optimized to have its focus spots approximately close to the light diffraction limit, illustrated in Figure 9. The circle diameter of the plot diagram represents the diameter of the Airy disc being equivalent to the diffraction limit of the light. Fig. 6 Hardware setup developed for the slit-scan chromatic confocal surface profilometry. Fig. 8 Optical simulation of a 20x chromatic objective Spectral axis 400nm 500nm 600nm 700nm Spatial axis Fig. 9 Optical simulations of the light focus spot diagrams with respect to various light wavelengths for the design of the chromatic objective. 2.4 Flow chart of the measurement method The flow chart of the developed measurement method is revealed in Figure 10. In here, a system calibration procedure including light intensity optimization, positioning verification of the translation stage and control of light exposure time for best image contrast is
4 performed to ensure an optimal spectrum imaging condition for chromatic scanning. Following this, implementation of a vertical scanning calibration using the measured object s surface is provided to establish the accurate mapping function between profile depth and light wavelength. With the calibrated function, the object can then be scanned to obtain its cross-section profiles by lateral scanning. 3. EXPERIMENTAL PROCESS AND RESULTS To attest the measurement accuracy of the developed measurement approach for multi-wavelength confocal surface profilometry, we conducted an experimental measurement on a calibrated step-height surface, shown in Figure 11. The overall measurable depth is 350 micrometers in the current system layout with the developed chromatic objective. By performing the measurement procedure described in the above session, Figure 11, (c) and (d) display the 3-D map, top view and cross-section profile being reconstructed from the step-height surface, respectively. From the analysis of the measured result, Table 1 illustrates the measurement accuracy and repeatability being obtained from a 30 time repeatability test. It indicates that the maximum measured error was less than % of the overall measurement range. In the current system design, the depth measurement range can be ranged between few to several hundred micrometers and the depth measurement resolution can reach down to 0.03% of the overall detection range. The measurement speed is determined by the light exposure time required for adequate spectrometry imaging. It is generally determined by the imaging CCD frame rate and the surface reflectivity condition of the tested object. Meanwhile, an industrial sample of a micro brightness enhance film (BEF) with a top height of 99.2 μm was also measured for verification of its feasibility on an industrial micro structure fabricated by Roll-to-Roll nanoimprinting processes. The measurement FOV was within a rectangular FOV area of 0.5*4.0 mm 2 for demonstration. The physical sample, 3-D shape, top view map and cross-section profile of the measured result are shown in Figure 12 -(d), respectively. From the measured results, it indicates that the developed method and system are capable of measuring insitu micro structures accurately. The measuring speed can reach up to 60 surface cross sections per second. System calibration Calibration curve Measuring sample Cross-section profile Lateral scanning 3D reconstruction Fig. 10 Flow chart of the developed measurement method. 4. CONCLUSIONS A slit-scan chromatic confocal surface profilometer was developed to achieve in-situ line-scan surface profilometry of micro structures without needing time-consuming vertical scanning operation. A chromatic optical objective can be designed and optimized by modulating various refractivity of multiple-wavelength light through optical lenses. A desirable measurable depth range can be obtained by designing the optical layout of the chromatic objective and it can be ranged from a few to several hundred micrometers. The detection resolution can be theoretically reaching down to 0.03% of the overall detection range. From the experimental tests, it was verified that the maximum measurement error can be controlled less than 0.1% of the overall measurement range with a repeatability of 52 nm within one standard deviation. The developed method and measurement system can be widely employed to in-situ microstructure profile measurement. The measurement speed of the system is currently limited by the frame rate of the imaging unit, which requires further development to achieve its best performance. Standard step-height surface Reconstructed 3-D map
5 (c) Top view of the 3-D map Reconstructed 3-D map (d) Cross-section profile Fig. 11 Measurement results of a standard step-height surface. (c) Top view of the 3-D map Table 1 Measurement accuracy evaluation from a 30-time test sample Standard height(μm) Measured height (μm) Error (%) Standard deviation (μm) Sample of a micro brightness enhancement film (BEF) (d) Cross-section profile of the 3-D map Fig. 12 Measurement results of of a micro BEF sample REFERENCES 1. Minsky, M., "Microscopy Apparatus," U.S. Patent, No.:3,013,467, Wilson, T., "Confocal Microscopy, " Academic, London, Bitte, F., Dussler, G., and Pfeifer, T., "3D micro-inspection goes DMD," Optics and Lasers in Engineering, Vol. 36, pp , Tanaami, T., Otsuki, S., Tomosada, N., Kosugi, Y., Shimizu, M., and Ishida, H., "High-speed 1-frame/ms scanning confocal microscope with a microlens and Nipkow disks," Applied Optics, Vol. 41, No. 22, pp , Ishihara, M., and Sasaki, H., "High speed surface measurement using a nonscanning multiple-beam confocal microscope," Optical Engineering, Vol. 38, Issue 6, pp , Raighne, A. M., Wang, J., Cabe, E. M., and Scharf, T., "Variable focus microlenses: Issues for confocal imaging," Proceedings of SPIE, Vol. 5827, pp , Seng, T. P., "Hybrid Confocal Microscopy," U.S. Patent, No.:5,880,844, Paul, L. C., Chen, S. P., Lijun, Z., and Yeshaiahu, F., "Singleshot depth-section imaging through chromatic slit-scan confocal microscopy," Applied Optics, Vol. 37, No. 28, pp , Wilson, T., Hewlett, S. J., and Sheppard, C. J. R., "Use of objective lenses with slit pupil functions in the imaging of line structures," Applied Optics, Vol. 29, No. 31, pp , 1990.
Quasi one-shot full-field surface profilometry using digital diffractive-confocal imaging correlation microscope
Quasi one-shot full-field surface profilometry using digital diffractive-confocal imaging correlation microscope Duc Trung Nguyen 1, Liang-Chia Chen* 1,2, Nguyen Dinh Nguyen 1 1 Mechanical Engineering
More informationInnovative full-field chromatic confocal microscopy using multispectral sensors
Innovative full-field chromatic confocal microscopy using multispectral sensors Liang-Chia Chen 1, 2, a#, Pei-Ju Tan 2, b, Chih-Jer Lin 2,c, Duc Trung Nguyen 1,d, Yu-Shuan Chou 1,e, Nguyen Dinh Nguyen
More informationA 3D Profile Parallel Detecting System Based on Differential Confocal Microscopy. Y.H. Wang, X.F. Yu and Y.T. Fei
Key Engineering Materials Online: 005-10-15 ISSN: 166-9795, Vols. 95-96, pp 501-506 doi:10.408/www.scientific.net/kem.95-96.501 005 Trans Tech Publications, Switzerland A 3D Profile Parallel Detecting
More informationHigh-speed 1-frame ms scanning confocal microscope with a microlens and Nipkow disks
High-speed 1-framems scanning confocal microscope with a microlens and Nipkow disks Takeo Tanaami, Shinya Otsuki, Nobuhiro Tomosada, Yasuhito Kosugi, Mizuho Shimizu, and Hideyuki Ishida We have developed
More informationSingle-shot depth-section imaging through chromatic slit-scan confocal microscopy
Single-shot depth-section imaging through chromatic slit-scan confocal microscopy Paul C. Lin, Pang-Chen Sun, Lijun Zhu, and Yeshaiahu Fainman A chromatic confocal microscope constructed with a white-light
More informationNontranslational three-dimensional profilometry by chromatic confocal microscopy with dynamically configurable micromirror scanning
Nontranslational three-dimensional profilometry by chromatic confocal microscopy with dynamically configurable micromirror scanning Sungdo Cha, Paul C. Lin, Lijun Zhu, Pang-Chen Sun, and Yeshaiahu Fainman
More informationPoint Spread Function. Confocal Laser Scanning Microscopy. Confocal Aperture. Optical aberrations. Alternative Scanning Microscopy
Bi177 Lecture 5 Adding the Third Dimension Wide-field Imaging Point Spread Function Deconvolution Confocal Laser Scanning Microscopy Confocal Aperture Optical aberrations Alternative Scanning Microscopy
More informationDevelopment of innovative fringe locking strategies for vibration-resistant white light vertical scanning interferometry (VSI)
Development of innovative fringe locking strategies for vibration-resistant white light vertical scanning interferometry (VSI) Liang-Chia Chen 1), Abraham Mario Tapilouw 1), Sheng-Lih Yeh 2), Shih-Tsong
More informationConfocal principle for macro- and microscopic surface and defect analysis
Confocal principle for macro- and microscopic surface and defect analysis Hans J. Tiziani, FELLOW SPIE Michael Wegner Daniela Steudle Institut für Technische Optik Pfaffenwaldring 9 70569 Stuttgart, Germany
More informationExam 4. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.
Name: Class: Date: Exam 4 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Mirages are a result of which physical phenomena a. interference c. reflection
More informationConfocal Imaging Through Scattering Media with a Volume Holographic Filter
Confocal Imaging Through Scattering Media with a Volume Holographic Filter Michal Balberg +, George Barbastathis*, Sergio Fantini % and David J. Brady University of Illinois at Urbana-Champaign, Urbana,
More informationDIMENSIONAL MEASUREMENT OF MICRO LENS ARRAY WITH 3D PROFILOMETRY
DIMENSIONAL MEASUREMENT OF MICRO LENS ARRAY WITH 3D PROFILOMETRY Prepared by Benjamin Mell 6 Morgan, Ste156, Irvine CA 92618 P: 949.461.9292 F: 949.461.9232 nanovea.com Today's standard for tomorrow's
More informationParallel Mode Confocal System for Wafer Bump Inspection
Parallel Mode Confocal System for Wafer Bump Inspection ECEN5616 Class Project 1 Gao Wenliang wen-liang_gao@agilent.com 1. Introduction In this paper, A parallel-mode High-speed Line-scanning confocal
More informationOptimal Pupil Design for Confocal Microscopy
Optimal Pupil Design for Confocal Microscopy Yogesh G. Patel 1, Milind Rajadhyaksha 3, and Charles A. DiMarzio 1,2 1 Department of Electrical and Computer Engineering, 2 Department of Mechanical and Industrial
More informationTesting Aspheric Lenses: New Approaches
Nasrin Ghanbari OPTI 521 - Synopsis of a published Paper November 5, 2012 Testing Aspheric Lenses: New Approaches by W. Osten, B. D orband, E. Garbusi, Ch. Pruss, and L. Seifert Published in 2010 Introduction
More informationattocfm I for Surface Quality Inspection NANOSCOPY APPLICATION NOTE M01 RELATED PRODUCTS G
APPLICATION NOTE M01 attocfm I for Surface Quality Inspection Confocal microscopes work by scanning a tiny light spot on a sample and by measuring the scattered light in the illuminated volume. First,
More informationThree-dimensional quantitative phase measurement by Commonpath Digital Holographic Microscopy
Available online at www.sciencedirect.com Physics Procedia 19 (2011) 291 295 International Conference on Optics in Precision Engineering and Nanotechnology Three-dimensional quantitative phase measurement
More informationDevelopment of a High-speed Super-resolution Confocal Scanner
Development of a High-speed Super-resolution Confocal Scanner Takuya Azuma *1 Takayuki Kei *1 Super-resolution microscopy techniques that overcome the spatial resolution limit of conventional light microscopy
More informationInstructions for the Experiment
Instructions for the Experiment Excitonic States in Atomically Thin Semiconductors 1. Introduction Alongside with electrical measurements, optical measurements are an indispensable tool for the study of
More informationBe aware that there is no universal notation for the various quantities.
Fourier Optics v2.4 Ray tracing is limited in its ability to describe optics because it ignores the wave properties of light. Diffraction is needed to explain image spatial resolution and contrast and
More informationREAL TIME THICKNESS MEASUREMENT OF A MOVING WIRE
REAL TIME THICKNESS MEASUREMENT OF A MOVING WIRE Bini Babu 1, Dr. Ashok Kumar T 2 1 Optoelectronics and communication systems, 2 Associate Professor Model Engineering college, Thrikkakara, Ernakulam, (India)
More informationOptical Components for Laser Applications. Günter Toesko - Laserseminar BLZ im Dezember
Günter Toesko - Laserseminar BLZ im Dezember 2009 1 Aberrations An optical aberration is a distortion in the image formed by an optical system compared to the original. It can arise for a number of reasons
More informationConfocal microscopy using variable-focal-length microlenses and an optical fiber bundle
Published in Applied Optics 44, issue 28, 5928-5936, 2005 which should be used for any reference to this work 1 Confocal microscopy using variable-focal-length microlenses and an optical fiber bundle Lisong
More informationBEAM HALO OBSERVATION BY CORONAGRAPH
BEAM HALO OBSERVATION BY CORONAGRAPH T. Mitsuhashi, KEK, TSUKUBA, Japan Abstract We have developed a coronagraph for the observation of the beam halo surrounding a beam. An opaque disk is set in the beam
More informationSupplementary Materials
Supplementary Materials In the supplementary materials of this paper we discuss some practical consideration for alignment of optical components to help unexperienced users to achieve a high performance
More informationMeasurement of the Modulation Transfer Function (MTF) of a camera lens. Laboratoire d Enseignement Expérimental (LEnsE)
Measurement of the Modulation Transfer Function (MTF) of a camera lens Aline Vernier, Baptiste Perrin, Thierry Avignon, Jean Augereau, Lionel Jacubowiez Institut d Optique Graduate School Laboratoire d
More informationOptical design of a high resolution vision lens
Optical design of a high resolution vision lens Paul Claassen, optical designer, paul.claassen@sioux.eu Marnix Tas, optical specialist, marnix.tas@sioux.eu Prof L.Beckmann, l.beckmann@hccnet.nl Summary:
More informationConfocal Microscopy and Related Techniques
Confocal Microscopy and Related Techniques Chau-Hwang Lee Associate Research Fellow Research Center for Applied Sciences, Academia Sinica 128 Sec. 2, Academia Rd., Nankang, Taipei 11529, Taiwan E-mail:
More informationOptical Coherence: Recreation of the Experiment of Thompson and Wolf
Optical Coherence: Recreation of the Experiment of Thompson and Wolf David Collins Senior project Department of Physics, California Polytechnic State University San Luis Obispo June 2010 Abstract The purpose
More informationHigh Resolution Detection of Synchronously Determining Tilt Angle and Displacement of Test Plane by Blu-Ray Pickup Head
Available online at www.sciencedirect.com Physics Procedia 19 (2011) 296 300 International Conference on Optics in Precision Engineering and Narotechnology 2011 High Resolution Detection of Synchronously
More informationSensitive measurement of partial coherence using a pinhole array
1.3 Sensitive measurement of partial coherence using a pinhole array Paul Petruck 1, Rainer Riesenberg 1, Richard Kowarschik 2 1 Institute of Photonic Technology, Albert-Einstein-Strasse 9, 07747 Jena,
More informationIMAGE SENSOR SOLUTIONS. KAC-96-1/5" Lens Kit. KODAK KAC-96-1/5" Lens Kit. for use with the KODAK CMOS Image Sensors. November 2004 Revision 2
KODAK for use with the KODAK CMOS Image Sensors November 2004 Revision 2 1.1 Introduction Choosing the right lens is a critical aspect of designing an imaging system. Typically the trade off between image
More informationUsing molded chalcogenide glass technology to reduce cost in a compact wide-angle thermal imaging lens
Using molded chalcogenide glass technology to reduce cost in a compact wide-angle thermal imaging lens George Curatu a, Brent Binkley a, David Tinch a, and Costin Curatu b a LightPath Technologies, 2603
More informationExercise 8: Interference and diffraction
Physics 223 Name: Exercise 8: Interference and diffraction 1. In a two-slit Young s interference experiment, the aperture (the mask with the two slits) to screen distance is 2.0 m, and a red light of wavelength
More informationUnderstanding Optical Specifications
Understanding Optical Specifications Optics can be found virtually everywhere, from fiber optic couplings to machine vision imaging devices to cutting-edge biometric iris identification systems. Despite
More informationSupplementary Figure 1. Effect of the spacer thickness on the resonance properties of the gold and silver metasurface layers.
Supplementary Figure 1. Effect of the spacer thickness on the resonance properties of the gold and silver metasurface layers. Finite-difference time-domain calculations of the optical transmittance through
More informationPROCEEDINGS OF SPIE. Measurement of low-order aberrations with an autostigmatic microscope
PROCEEDINGS OF SPIE SPIEDigitalLibrary.org/conference-proceedings-of-spie Measurement of low-order aberrations with an autostigmatic microscope William P. Kuhn Measurement of low-order aberrations with
More informationInvestigation of an optical sensor for small angle detection
Investigation of an optical sensor for small angle detection usuke Saito, oshikazu rai and Wei Gao Nano-Metrology and Control Lab epartment of Nanomechanics Graduate School of Engineering, Tohoku University
More informationEE119 Introduction to Optical Engineering Spring 2003 Final Exam. Name:
EE119 Introduction to Optical Engineering Spring 2003 Final Exam Name: SID: CLOSED BOOK. THREE 8 1/2 X 11 SHEETS OF NOTES, AND SCIENTIFIC POCKET CALCULATOR PERMITTED. TIME ALLOTTED: 180 MINUTES Fundamental
More informationSystems Biology. Optical Train, Köhler Illumination
McGill University Life Sciences Complex Imaging Facility Systems Biology Microscopy Workshop Tuesday December 7 th, 2010 Simple Lenses, Transmitted Light Optical Train, Köhler Illumination What Does a
More informationImproving the Collection Efficiency of Raman Scattering
PERFORMANCE Unparalleled signal-to-noise ratio with diffraction-limited spectral and imaging resolution Deep-cooled CCD with excelon sensor technology Aberration-free optical design for uniform high resolution
More informationTest procedures Page: 1 of 5
Test procedures Page: 1 of 5 1 Scope This part of document establishes uniform requirements for measuring the numerical aperture of optical fibre, thereby assisting in the inspection of fibres and cables
More informationCharacteristics of point-focus Simultaneous Spatial and temporal Focusing (SSTF) as a two-photon excited fluorescence microscopy
Characteristics of point-focus Simultaneous Spatial and temporal Focusing (SSTF) as a two-photon excited fluorescence microscopy Qiyuan Song (M2) and Aoi Nakamura (B4) Abstracts: We theoretically and experimentally
More informationPhysics 431 Final Exam Examples (3:00-5:00 pm 12/16/2009) TIME ALLOTTED: 120 MINUTES Name: Signature:
Physics 431 Final Exam Examples (3:00-5:00 pm 12/16/2009) TIME ALLOTTED: 120 MINUTES Name: PID: Signature: CLOSED BOOK. TWO 8 1/2 X 11 SHEET OF NOTES (double sided is allowed), AND SCIENTIFIC POCKET CALCULATOR
More informationA broadband achromatic metalens for focusing and imaging in the visible
SUPPLEMENTARY INFORMATION Articles https://doi.org/10.1038/s41565-017-0034-6 In the format provided by the authors and unedited. A broadband achromatic metalens for focusing and imaging in the visible
More informationChapter Ray and Wave Optics
109 Chapter Ray and Wave Optics 1. An astronomical telescope has a large aperture to [2002] reduce spherical aberration have high resolution increase span of observation have low dispersion. 2. If two
More informationMaskless Lithography Based on Digital Micro-Mirror Device (DMD) with Double Sided Microlens and Spatial Filter Array
2017 2nd International Conference on Applied Mechanics, Electronics and Mechatronics Engineering (AMEME 2017) ISBN: 978-1-60595-497-4 Maskless Lithography Based on Digital Micro-Mirror Device (DMD) with
More informationDesign Description Document
UNIVERSITY OF ROCHESTER Design Description Document Flat Output Backlit Strobe Dare Bodington, Changchen Chen, Nick Cirucci Customer: Engineers: Advisor committee: Sydor Instruments Dare Bodington, Changchen
More informationECEN. Spectroscopy. Lab 8. copy. constituents HOMEWORK PR. Figure. 1. Layout of. of the
ECEN 4606 Lab 8 Spectroscopy SUMMARY: ROBLEM 1: Pedrotti 3 12-10. In this lab, you will design, build and test an optical spectrum analyzer and use it for both absorption and emission spectroscopy. The
More information3D light microscopy techniques
3D light microscopy techniques The image of a point is a 3D feature In-focus image Out-of-focus image The image of a point is not a point Point Spread Function (PSF) 1D imaging 1 1 2! NA = 0.5! NA 2D imaging
More informationNanoimprint lithography with a focused laser beam for the fabrication of micro-/nano-hybrid patterns
Supplementary Material (ESI) for Lab on a Chip This journal is The Royal Society of Chemistry 20XX Nanoimprint lithography with a focused laser beam for the fabrication of micro-/nano-hybrid patterns Hyungjun
More informationKit for building your own THz Time-Domain Spectrometer
Kit for building your own THz Time-Domain Spectrometer 16/06/2016 1 Table of contents 0. Parts for the THz Kit... 3 1. Delay line... 4 2. Pulse generator and lock-in detector... 5 3. THz antennas... 6
More informationFRAUNHOFER AND FRESNEL DIFFRACTION IN ONE DIMENSION
FRAUNHOFER AND FRESNEL DIFFRACTION IN ONE DIMENSION Revised November 15, 2017 INTRODUCTION The simplest and most commonly described examples of diffraction and interference from two-dimensional apertures
More informationECEN 4606, UNDERGRADUATE OPTICS LAB
ECEN 4606, UNDERGRADUATE OPTICS LAB Lab 2: Imaging 1 the Telescope Original Version: Prof. McLeod SUMMARY: In this lab you will become familiar with the use of one or more lenses to create images of distant
More informationExamination, TEN1, in courses SK2500/SK2501, Physics of Biomedical Microscopy,
KTH Applied Physics Examination, TEN1, in courses SK2500/SK2501, Physics of Biomedical Microscopy, 2009-06-05, 8-13, FB51 Allowed aids: Compendium Imaging Physics (handed out) Compendium Light Microscopy
More informationTesting Aspherics Using Two-Wavelength Holography
Reprinted from APPLIED OPTICS. Vol. 10, page 2113, September 1971 Copyright 1971 by the Optical Society of America and reprinted by permission of the copyright owner Testing Aspherics Using Two-Wavelength
More informationComparison of resolution specifications for micro- and nanometer measurement techniques
P4.5 Comparison of resolution specifications for micro- and nanometer measurement techniques Weckenmann/Albert, Tan/Özgür, Shaw/Laura, Zschiegner/Nils Chair Quality Management and Manufacturing Metrology
More informationGuide to SPEX Optical Spectrometer
Guide to SPEX Optical Spectrometer GENERAL DESCRIPTION A spectrometer is a device for analyzing an input light beam into its constituent wavelengths. The SPEX model 1704 spectrometer covers a range from
More informationUV EXCIMER LASER BEAM HOMOGENIZATION FOR MICROMACHINING APPLICATIONS
Optics and Photonics Letters Vol. 4, No. 2 (2011) 75 81 c World Scientific Publishing Company DOI: 10.1142/S1793528811000226 UV EXCIMER LASER BEAM HOMOGENIZATION FOR MICROMACHINING APPLICATIONS ANDREW
More informationLaser Beam Analysis Using Image Processing
Journal of Computer Science 2 (): 09-3, 2006 ISSN 549-3636 Science Publications, 2006 Laser Beam Analysis Using Image Processing Yas A. Alsultanny Computer Science Department, Amman Arab University for
More informationReflecting optical system to increase signal intensity. in confocal microscopy
Reflecting optical system to increase signal intensity in confocal microscopy DongKyun Kang *, JungWoo Seo, DaeGab Gweon Nano Opto Mechatronics Laboratory, Dept. of Mechanical Engineering, Korea Advanced
More information(12) United States Patent (10) Patent No.: US 6,525,828 B1
USOO6525828B1 (12) United States Patent (10) Patent No.: US 6,525,828 B1 Grosskopf (45) Date of Patent: *Feb. 25, 2003 (54) CONFOCAL COLOR 5,978,095 A 11/1999 Tanaami... 356/445 6,031,661. A 2/2000 Tanaami...
More informationRon Liu OPTI521-Introductory Optomechanical Engineering December 7, 2009
Synopsis of METHOD AND APPARATUS FOR IMPROVING VISION AND THE RESOLUTION OF RETINAL IMAGES by David R. Williams and Junzhong Liang from the US Patent Number: 5,777,719 issued in July 7, 1998 Ron Liu OPTI521-Introductory
More informationCriteria for Optical Systems: Optical Path Difference How do we determine the quality of a lens system? Several criteria used in optical design
Criteria for Optical Systems: Optical Path Difference How do we determine the quality of a lens system? Several criteria used in optical design Computer Aided Design Several CAD tools use Ray Tracing (see
More informationSlit. Spectral Dispersion
Testing Method of Off-axis Parabolic Cylinder Mirror for FIMS K. S. Ryu a,j.edelstein b, J. B. Song c, Y. W. Lee c, J. S. Chae d, K. I. Seon e, I. S. Yuk e,e.korpela b, J. H. Seon a,u.w. Nam e, W. Han
More informationOptical Characterization and Defect Inspection for 3D Stacked IC Technology
Minapad 2014, May 21 22th, Grenoble; France Optical Characterization and Defect Inspection for 3D Stacked IC Technology J.Ph.Piel, G.Fresquet, S.Perrot, Y.Randle, D.Lebellego, S.Petitgrand, G.Ribette FOGALE
More informationFabrication of microstructures on photosensitive glass using a femtosecond laser process and chemical etching
Fabrication of microstructures on photosensitive glass using a femtosecond laser process and chemical etching C. W. Cheng* 1, J. S. Chen* 2, P. X. Lee* 2 and C. W. Chien* 1 *1 ITRI South, Industrial Technology
More informationSupplementary Figure 1. GO thin film thickness characterization. The thickness of the prepared GO thin
Supplementary Figure 1. GO thin film thickness characterization. The thickness of the prepared GO thin film is characterized by using an optical profiler (Bruker ContourGT InMotion). Inset: 3D optical
More informationStudy on Imaging Quality of Water Ball Lens
2017 2nd International Conference on Mechatronics and Information Technology (ICMIT 2017) Study on Imaging Quality of Water Ball Lens Haiyan Yang1,a,*, Xiaopan Li 1,b, 1,c Hao Kong, 1,d Guangyang Xu and1,eyan
More informationWavefront sensing by an aperiodic diffractive microlens array
Wavefront sensing by an aperiodic diffractive microlens array Lars Seifert a, Thomas Ruppel, Tobias Haist, and Wolfgang Osten a Institut für Technische Optik, Universität Stuttgart, Pfaffenwaldring 9,
More information3.0 Alignment Equipment and Diagnostic Tools:
3.0 Alignment Equipment and Diagnostic Tools: Alignment equipment The alignment telescope and its use The laser autostigmatic cube (LACI) interferometer A pin -- and how to find the center of curvature
More informationPowerful DMD-based light sources with a high throughput virtual slit Arsen R. Hajian* a, Ed Gooding a, Thomas Gunn a, Steven Bradbury a
Powerful DMD-based light sources with a high throughput virtual slit Arsen R. Hajian* a, Ed Gooding a, Thomas Gunn a, Steven Bradbury a a Hindsight Imaging Inc., 233 Harvard St. #316, Brookline MA 02446
More informationEUV Plasma Source with IR Power Recycling
1 EUV Plasma Source with IR Power Recycling Kenneth C. Johnson kjinnovation@earthlink.net 1/6/2016 (first revision) Abstract Laser power requirements for an EUV laser-produced plasma source can be reduced
More informationAberrations of a lens
Aberrations of a lens 1. What are aberrations? A lens made of a uniform glass with spherical surfaces cannot form perfect images. Spherical aberration is a prominent image defect for a point source on
More informationOptics and Lasers. Matt Young. Including Fibers and Optical Waveguides
Matt Young Optics and Lasers Including Fibers and Optical Waveguides Fourth Revised Edition With 188 Figures Springer-Verlag Berlin Heidelberg New York London Paris Tokyo Hong Kong Barcelona Budapest Contents
More informationDevelopment of Laser Confocal Microscopy for Internal Defect Measurement
Development of Laser Confocal Microscopy for Internal Defect Measurement Chia-Liang Yeh*, Fu-Cheng Yang, Wei-Hsiung Tsai, and Keng-Li Lin Center for Measurement Standards, Industrial Technology Research
More informationSome of the important topics needed to be addressed in a successful lens design project (R.R. Shannon: The Art and Science of Optical Design)
Lens design Some of the important topics needed to be addressed in a successful lens design project (R.R. Shannon: The Art and Science of Optical Design) Focal length (f) Field angle or field size F/number
More informationWaveMaster IOL. Fast and Accurate Intraocular Lens Tester
WaveMaster IOL Fast and Accurate Intraocular Lens Tester INTRAOCULAR LENS TESTER WaveMaster IOL Fast and accurate intraocular lens tester WaveMaster IOL is an instrument providing real time analysis of
More informationPROCEEDINGS OF SPIE. Measurement of the modulation transfer function (MTF) of a camera lens
PROCEEDINGS OF SPIE SPIEDigitalLibrary.org/conference-proceedings-of-spie Measurement of the modulation transfer function (MTF) of a camera lens Aline Vernier, Baptiste Perrin, Thierry Avignon, Jean Augereau,
More informationChapter 36: diffraction
Chapter 36: diffraction Fresnel and Fraunhofer diffraction Diffraction from a single slit Intensity in the single slit pattern Multiple slits The Diffraction grating X-ray diffraction Circular apertures
More informationApplied Optics. , Physics Department (Room #36-401) , ,
Applied Optics Professor, Physics Department (Room #36-401) 2290-0923, 019-539-0923, shsong@hanyang.ac.kr Office Hours Mondays 15:00-16:30, Wednesdays 15:00-16:30 TA (Ph.D. student, Room #36-415) 2290-0921,
More informationDynamic beam shaping with programmable diffractive optics
Dynamic beam shaping with programmable diffractive optics Bosanta R. Boruah Dept. of Physics, GU Page 1 Outline of the talk Introduction Holography Programmable diffractive optics Laser scanning confocal
More informationPractical Flatness Tech Note
Practical Flatness Tech Note Understanding Laser Dichroic Performance BrightLine laser dichroic beamsplitters set a new standard for super-resolution microscopy with λ/10 flatness per inch, P-V. We ll
More informationKatarina Logg, Kristofer Bodvard, Mikael Käll. Dept. of Applied Physics. 12 September Optical Microscopy. Supervisor s signature:...
Katarina Logg, Kristofer Bodvard, Mikael Käll Dept. of Applied Physics 12 September 2007 O1 Optical Microscopy Name:.. Date:... Supervisor s signature:... Introduction Over the past decades, the number
More informationShaping light in microscopy:
Shaping light in microscopy: Adaptive optical methods and nonconventional beam shapes for enhanced imaging Martí Duocastella planet detector detector sample sample Aberrated wavefront Beamsplitter Adaptive
More informationExperiment 1: Fraunhofer Diffraction of Light by a Single Slit
Experiment 1: Fraunhofer Diffraction of Light by a Single Slit Purpose 1. To understand the theory of Fraunhofer diffraction of light at a single slit and at a circular aperture; 2. To learn how to measure
More informationA novel tunable diode laser using volume holographic gratings
A novel tunable diode laser using volume holographic gratings Christophe Moser *, Lawrence Ho and Frank Havermeyer Ondax, Inc. 85 E. Duarte Road, Monrovia, CA 9116, USA ABSTRACT We have developed a self-aligned
More informationSupplementary Information for: Immersion Meta-lenses at Visible Wavelengths for Nanoscale Imaging
Supplementary Information for: Immersion Meta-lenses at Visible Wavelengths for Nanoscale Imaging Wei Ting Chen 1,, Alexander Y. Zhu 1,, Mohammadreza Khorasaninejad 1, Zhujun Shi 2, Vyshakh Sanjeev 1,3
More informationMulti-kW high-brightness fiber coupled diode laser based on two dimensional stacked tailored diode bars
Multi-kW high-brightness fiber coupled diode laser based on two dimensional stacked tailored diode bars Andreas Bayer*, Andreas Unger, Bernd Köhler, Matthias Küster, Sascha Dürsch, Heiko Kissel, David
More informationThe spectral colours of nanometers
Reprint from the journal Mikroproduktion 3/2005 Berthold Michelt and Jochen Schulze The spectral colours of nanometers Precitec Optronik GmbH Raiffeisenstraße 5 D-63110 Rodgau Phone: +49 (0) 6106 8290-14
More informationPhysicsAndMathsTutor.com 1
PhysicsAndMathsTutor.com 1 Q1. Just over two hundred years ago Thomas Young demonstrated the interference of light by illuminating two closely spaced narrow slits with light from a single light source.
More informationApplying of refractive beam shapers of circular symmetry to generate non-circular shapes of homogenized laser beams
- 1 - Applying of refractive beam shapers of circular symmetry to generate non-circular shapes of homogenized laser beams Alexander Laskin a, Vadim Laskin b a MolTech GmbH, Rudower Chaussee 29-31, 12489
More informationTECHSPEC COMPACT FIXED FOCAL LENGTH LENS
Designed for use in machine vision applications, our TECHSPEC Compact Fixed Focal Length Lenses are ideal for use in factory automation, inspection or qualification. These machine vision lenses have been
More informationEE119 Introduction to Optical Engineering Fall 2009 Final Exam. Name:
EE119 Introduction to Optical Engineering Fall 2009 Final Exam Name: SID: CLOSED BOOK. THREE 8 1/2 X 11 SHEETS OF NOTES, AND SCIENTIFIC POCKET CALCULATOR PERMITTED. TIME ALLOTTED: 180 MINUTES Fundamental
More informationBringing Answers to the Surface
3D Bringing Answers to the Surface 1 Expanding the Boundaries of Laser Microscopy Measurements and images you can count on. Every time. LEXT OLS4100 Widely used in quality control, research, and development
More informationSPECTRAL SCANNER. Recycling
SPECTRAL SCANNER The Spectral Scanner, produced on an original project of DV s.r.l., is an instrument to acquire with extreme simplicity the spectral distribution of the different wavelengths (spectral
More informationImaging with microlenslet arrays
Imaging with microlenslet arrays Vesselin Shaoulov, Ricardo Martins, and Jannick Rolland CREOL / School of Optics University of Central Florida Orlando, Florida 32816 Email: vesko@odalab.ucf.edu 1. ABSTRACT
More informationBig League Cryogenics and Vacuum The LHC at CERN
Big League Cryogenics and Vacuum The LHC at CERN A typical astronomical instrument must maintain about one cubic meter at a pressure of
More informationNanoSpective, Inc Progress Drive Suite 137 Orlando, Florida
TEM Techniques Summary The TEM is an analytical instrument in which a thin membrane (typically < 100nm) is placed in the path of an energetic and highly coherent beam of electrons. Typical operating voltages
More informationLEOK-3 Optics Experiment kit
LEOK-3 Optics Experiment kit Physical optics, geometrical optics and fourier optics Covering 26 experiments Comprehensive documents Include experiment setups, principles and procedures Cost effective solution
More information