■ CONTENTS General Information: Books, Reviews, and Conferences 640 Fundamentals 641 Interaction of Laser Beam with Matter 641 Factors Affecting Laser Ablation and LaserInduced Plasma Formation 642 Influence of Target on the Laser-Induced Plasmas 642 Influence of Laser Parameters on the LaserInduced Plasmas 643 Laser Wavelength (λ) 643 Laser Pulse Duration (τ) 643 Laser Pulse Energy (E) 645 Influence of Ambient Gas on the Laser-Induced Plasmas 645 LIBS Methods 647 Double Pulse LIBS 647 Femtosecond LIBS 651 Resonant LIBS 652 Ranging Approaches 652 Applications 654 Surface Inspection, Depth Profiling, and LIBS Imaging 654 Cultural Heritage 654 Industrial Analysis 655 Environmental Monitoring 656 Biomedical and Pharmaceutical Analysis 658 Security and Forensics 659 Analysis of Liquids and Submerged Solids 660 Space Exploration and Isotopic Analysis 662 Space Exploration 662 Isotopic Analysis 662 Conclusions and Future Outlook 663 Author Information 664 Corresponding Author 664 Notes 664 Biographies 664 Acknowledgments 664 References 664

Laser-induced breakdown spectroscopy.

Manufacturing and measurement of freeform optics

On-machine and in-process surface metrology for precision manufacturing

A software configurable optical test system (SCOTS) based on the geometry of the fringe reflection or phase measuring deflectometry method was developed for rapidly, robustly, and accurately measuring large, highly aspherical shapes such as solar collectors and primary mirrors for astronomical telescopes. In addition to using phase shifting methods for data collection and reduction, we explore the test from the point view of performing traditional optical testing methods, such as Hartmann or Hartmann-Shack tests, in a reverse way. Using this concept, the slope data calculation and unwrapping in the test can also be done with centroiding and line-scanning methods. These concepts expand the test to work in more general situations where fringe illumination is not practical. Experimental results show that the test can be implemented without complex calibration for many applications by taking the geometric advantage of working near the center curvature of the test part. The results also show that the test has a large dynamic range, can achieve measurement accuracy comparable with interferometric methods, and can provide a good complement to interferometric tests in certain circumstances. A variation of this method is also useful for measuring refractive optics and optical systems. As such, SCOTS provides optical manufacturers with a new tool for performing quantitative full field system evaluation.

Software configurable optical test system: a computerized reverse Hartmann test

THE OPTO-MECHANICAL DESIGN PROCESS Introduction Conceptualization Performance Specifications and Design Constraints Preliminary Design Design Analysis and Computer Modeling Error Budgets and Tolerances Experimental Modeling Finalizing the Design Design Reviews Manufacturing the Instrument Evaluating the End Product Documenting the Design References ENVIRONMENTAL INFLUENCES Introduction Parameters of Concern Environmental Testing of Optics References OPTO-MECHANICAL CHARACTERISTICS OF MATERIALS Introduction Materials for Refracting Optics Materials for Reflecting Optics Materials for Mechanical Components Adhesives Sealants Special Coatings for Opto-Mechanical Materials Techniques for Manufacturing Opto-Mechanical Parts References MOUNTING INDIVIDUAL LENSES Introduction Considerations of Centered Optics Cost Impacts of Fabrication Tolerances Lens Weight and Center of Gravity Location Mounting Individual Low-Precision Lenses Mountings for Lenses with Curved Rims Mountings Interfacing with Spherical Surfaces Elastomeric Mountings for Lenses Mounting Lenses on Flexures Alignment of the Individual Lens Mounting Plastic Lenses References MOUNTING MULTIPLE LENSES Introduction Multielement Spacing Considerations Examples of Lens Assemblies with No Moving Parts Examples of Lens Assemblies Containing Moving Parts Lathe Assembly Techniques Microscope Objectives Assemblies Using Plastic Parts Liquid Coupling of Lenses Catadioptric Assemblies Alignment of Multi-Lens Assemblies Alignment of Reflecting Telescope Systems References MOUNTING WINDOWS AND FILTERS Introduction Conventional Window Mounts Special Window Mounts Mounts for Shells and Domes Conformal Windows Filter Mounts Windows Subject to a Pressure Differential References DESIGNING AND MOUNTING PRISMS Introduction Geometric Relationships Designs for Typical Prisms Kinematic and Semikinematic Prism Mounting Principles Mounting Prisms by Clamping Mounting Prisms by Bonding Flexure Mounts for Prisms References DESIGN AND MOUNTING SMALL, NONMETALLIC MIRRORS, GRATINGS, AND PELLICLES Introduction General Considerations Semikinematic Mountings for Small Mirrors Mounting Mirrors by Bonding Flexure Mounts for Mirrors Multiple-Mirror Mounts Mountings for Gratings Pellicle Design and Mounting References LIGHTWEIGHT NONMETALLIC MIRROR DESIGN Introduction Material Considerations Core Cell Configurations Cast Ribbed Substrates Slotted-Strut and Fused Monolithic Substrates Frit-Bonded Substrates Low-Temperature Bonded Substrates Machined-Core Substrates Contoured-Back Solid Mirror Configurations Thin Face Sheet Mirror Configurations Scaling Relationships for Lightweight Mirrors References MOUNTING LARGE, HORIZONTAL-AXIS MIRRORS Introduction General Considerations of Gravity Effects V-Type Mounts Multipoint Edge Supports The Ideal Radial Mount Mercury Tube Mounts Strap and Roller-Chain Mounts Push-Pull Mounts Comparison of Dynamic Relaxation and Finite-Element Analysis Techniques References MOUNTING LARGE VERTICAL-AXIS MIRRORS Introduction Ring Mounts Air Bag (Bladder) Mounts Multiple-Point Supports Metrology Mounts References MOUNTING LARGE, VARIABLE-ORIENTATION MIRRORS Introduction Mechanical Flotation Mounts Hydraulic/Pneumatic Mounts Center-Mounted Mirrors Mounts for Double-Arch Mirrors Bipod Mirror Mounts Thin Face Sheet Mirror Mounts Mounts for Large Space-Borne Mirrors References DESIGN AND MOUNTING OF METALLIC MIRRORS Introduction General Considerations of Metal Mirrors Aluminum Mirrors Beryllium Mirrors Mirrors Made from Other Metals Mirrors with Foam and Metal Matrix Cores Plating of Metal Mirrors Single-Point Diamond Turning of Metal Mirrors Conventional Mountings for Metal Mirrors Integral Mountings for Metal Mirrors Flexure Mountings for Larger Metal Mirrors Interfacing Multiple SPDT Components to Facilitate Assembly and Alignment References OPTICAL INSTRUMENT STRUCTURAL DESIGN Introduction Rigid Housing Configurations Modular Design Principles and Examples A Structural Design for High Shock Loading Athermalized Structural Designs Geometries for Telescope Tube Structures References ANALYSIS OF THE OPTO-MECHANICAL DESIGN Introduction Failure Predictions for Optics Stress Generation at Opto-Mechanical Interfaces Parametric Comparisons of Annular Interface Types Bending Effects Due to Offset Annular Contacts Effects of Temperature Changes Effects of Temperature Gradients Stresses in Cemented and Bonded Optics Due to Temperature Changes Some Effects of Temperature Changes on Elastomerically Mounted Lenses References APPENDIX A: UNITS AND THEIR CONVERSION APPENDIX B: SUMMARY OF METHODS FOR TESTING OPTICAL COMPONENTS AND OPTICAL INSTRUMENTS UNDER ADVERSE ENVIRONMENTAL CONDITIONS APPENDIX C: HARDNESS OF MATERIALS APPENDIX D: GLOSSARY INDEX

Opto-mechanical systems design

Laser trackers have been developed that project laser beams and use optical systems to provide three dimensional coordinate measurements. The laser trackers incorporate a servo system to steer a laser beam so that it tracks a retroreflector, such as a corner cube. The line of sight gimbal angles and the radial distance to the retroreflector are used to determine the coordinates of the retroreflector relative to the tracker. In this paper, we explore the use of the laser tracker to define the metrology for aligning optical systems, including the use of mirrors and windows. We discuss how to optimize the geometry to take advantage of the tracker’s most accurate measurements. We show how to use the tracker for measuring angles as well as points.

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Use of a commercial laser tracker for optical alignment

In a previous paper, the University of Arizona (UA) has developed a measurement technique called: Software Configurable Optical Test System (SCOTS) based on the principle of reflection deflectometry. In this paper, we present results of this very efficient optical metrology method applied to the metrology of X-ray mirrors. We used this technique to measure surface slope errors with precision and accuracy better than 100 nrad (rms) and ~200 nrad (rms), respectively, with a lateral resolution of few mm or less. We present results of the calibration of the metrology systems, discuss their accuracy and address the precision in measuring a spherical mirror.

Non-null full field X-ray mirror metrology using SCOTS: a reflection deflectometry approach

A software configurable optical test system (SCOTS) based on deflectometry was developed at the University of Arizona for rapidly, robustly, and accurately measuring precision aspheric and freeform surfaces. SCOTS uses a camera with an external stop to realize a Hartmann test in reverse. With the external camera stop as the reference, a coordinate measuring machine can be used to calibrate the SCOTS test geometry to a high accuracy. Systematic errors from the camera are carefully investigated and controlled. Camera pupil imaging aberration is removed with the external aperture stop. Imaging aberration and other inherent errors are suppressed with an N -rotation test. The performance of the SCOTS test is demonstrated with the measurement results from a 5-m-diameter Large Synoptic Survey Telescope tertiary mirror and an 8.4-m diameter Giant Magellan Telescope primary mirror. The results show that SCOTS can be used as a large-dynamic-range, high-precision, and non-null test method for precision aspheric and freeform surfaces. The SCOTS test can achieve measurement accuracy comparable to traditional interferometric tests.

Aspheric and freeform surfaces metrology with software configurable optical test system: a computerized reverse Hartmann test

A software configurable optical test system (SCOTS) based on fringe reflection was implemented for measuring the
primary mirror segments of the Giant Magellan Telescope (GMT). The system uses modulated fringe patterns on an
LCD monitor as the source, and captures data with a CCD camera and calibrated imaging optics. The large dynamic
range of SCOTS provides good measurement of regions with large slopes that cannot be captured reliably with
interferometry. So the principal value of the SCOTS test for GMT is to provide accurate measurements that extend
clear to the edge of the glass, even while the figure is in a rough state of figure, where the slopes are still high.
Accurate calibration of the geometry and the mapping also enable the SCOTS test to achieve accuracy that is
comparable measurement accuracy to the interferometric null test for the small- and middle- spatial scale errors in
the GMT mirror.

Peng Su

Papers

Software configurable optical test system: a computerized reverse Hartmann test

Use of a commercial laser tracker for optical alignment

Non-null full field X-ray mirror metrology using SCOTS: a reflection deflectometry approach

Aspheric and freeform surfaces metrology with software configurable optical test system: a computerized reverse Hartmann test

SCOTS: A reverse Hartmann test with high dynamic range for Giant Magellan Telescope primary mirror segments