Building Electro-Optical Systems -Making it All Work

Cover
Title Page
Copyright
Contents
Preface
Acknowledgments
Chapter 1 Basic Optical Calculations
1.1 Introduction
1.2 Wave Propagation
1.2.1 Maxwell's Equations and Plane Waves
1.2.2 Plane Waves in Material Media
1.2.3 Phase Matching
1.2.4 Refraction, Snell's Law, and the Fresnel Coefficients
1.2.5 Brewster's Angle
1.2.6 Total Internal Reflection
1.2.7 Goos–Hänchen Shift
1.2.8 Circular and Elliptical Polarization
1.2.9 Optical Loss
1.3 Calculating Wave Propagation in Real Life
1.3.1 Scalar Optics
1.3.2 Paraxial Propagation
1.3.3 Gaussian Beams
1.3.4 The Debye Approximation, Fresnel Zones, and The Fresnel Number
1.3.5 Ray Optics
1.3.6 Lenses
1.3.7 Aperture, Field Angle, and Stops
1.3.8 Fourier Transform Relations
1.3.9 Fourier Imaging
1.3.10 The Pupil
1.3.11 Pupil Problems
1.3.12 Connecting Wave and Ray Optics: ABCD Matrices
1.3.13 Extended ABCD Matrices
1.3.14 ABCD Matrices and Wave Optics
1.3.15 Source Angular Distribution: Isotropic and Lambertian Sources
1.3.16 Solid Angle
1.3.17 Étendue: How Much Light Can I Get?
1.3.18 What Is “Resolution”?
1.4 Detection
1.5 Coherent Detection
1.5.1 Interference
1.5.2 Coherent Detection and Shot Noise: The Rule of One
1.5.3 Spatial Selectivity of Coherent Detection
1.5.4 Optical Modes, Antennas, and Thermodynamics
1.6 Interferometers
1.6.1 Two‐Beam Interferometers
1.6.2 Multiple‐Beam Interferometers: Fabry–Perots
1.6.3 Focused‐Beam Resonators
1.7 Photon Budgets and Operating Specifications
1.7.1 Basis
1.8 Signal Processing Strategy
1.8.1 Analog Signal Processing
1.8.2 Back‐End Processing Strategy
1.8.3 Putting It All Together
Chapter 2 Sources And Illuminators
2.1 Introduction
2.2 The Spectrum
2.2.1 Visible Light
2.2.2 Ultraviolet
2.2.3 Infrared
2.3 Radiometry
2.4 Continuum Sources
2.4.1 Black Body Radiators
2.4.2 Radiance Conservation and the Second Law of Thermodynamics
2.4.3 Tungsten Bulbs
2.4.4 Glow Bulbs and Globars
2.5 Interlude: Coherence
2.5.1 Speckle
2.5.2 Imaging Calculations with Partially Coherent Light
2.5.3 Gotcha: Coherence Fluctuations at Finite Bandwidth
2.5.4 Measuring Laser Noise in Practice
2.5.5 Gotcha: Aerosol Particles and Laser Noise
2.6 More Sources
2.6.1 LEDs
2.6.1.1 LED Noise
2.6.2 Superluminescent Diodes
2.6.3 Other Amplified Spontaneous Emission (ASE) Devices
2.6.4 High‐Pressure Arc Lamps
2.6.5 Flashlamps
2.6.6 Spark and Avalanche Sources
2.7 Incoherent Line Sources
2.7.1 Low‐Pressure Discharges
2.8 Using Low‐Coherence Sources: Condensers
2.8.1 Radiometry of Imaging Systems
2.8.2 The Condenser Problem
2.9 Lasers
2.9.1 Mode Structure
2.9.2 Schawlow–Townes Line width
2.9.3 Relaxation Oscillation
2.10 Gas Lasers
2.11 Solid‐State Lasers
2.11.1 Modelocked Lasers, Parametric Oscillators, and Other Exotica
2.12 Diode Lasers
2.12.1 Visible Diode Lasers
2.12.2 Distributed Feedback and Distributed Bragg Reflector
2.12.3 Tuning Properties
2.12.4 Mode Jumps
2.12.5 Regions of Stability
2.12.6 Temperature Behavior
2.12.7 Diode Laser Life
2.12.8 Checking the Mode Structure
2.12.9 Vertical‐Cavity Surface‐Emitting Lasers
2.12.10 Better‐Behaved VCSELS
2.12.11 Modulation Behavior
2.12.12 ESD Sensitivity
2.12.13 Difficulty in Collimating
2.12.14 Other Diode Laser Foibles
2.13 Laser Noise
2.13.1 Intensity Noise
2.13.2 Frequency Noise
2.13.3 Mode Hopping
2.13.4 Gotcha: Mode Jumps in Multimode Diodes
2.13.5 Mode‐Partition Noise
2.13.6 Gotcha: Surface Near a Focus
2.13.7 Pulling
2.13.8 Self‐Locking
2.13.9 Mode Beats
2.13.10 Power Supply Ripple and Pump Noise
2.13.11 Microphonics
2.13.12 Frequency Noise
2.13.13 Spatial and Wiggle Noise
2.13.14 Polarization Noise
2.13.15 Etalon Fringes and Laser Noise
2.14 Diode Laser Coherence Control
2.14.1 External Cavity Diode Lasers
2.14.2 Injection Locking and MOPA
2.14.3 Strong UHF Modulation
2.14.4 Weaker Phase Modulation
Chapter 3 Optical Detection
3.1 Introduction
3.2 Signal‐to‐Noise Ratios
3.2.1 Square Law Detectors
3.2.2 Photons
3.3 Detector Figures of Merit
3.3.1 Quantum Efficiency
3.3.2 Responsivity
3.3.3 Leakage Current
3.3.4 Noise‐Equivalent Power (NEP)
3.3.5 Specific Detectivity (D*)
3.3.6 Capacitance
3.3.6.1 Reverse Bias
3.3.7 Spectral Response
3.3.8 Spatial Uniformity
3.3.9 Series Resistance
3.3.10 Gotcha: RC Phase Shifts in the epi
3.3.11 Diffusion‐Limited Response
3.3.12 Another Gotcha: Ring Contact Photodiodes and Diffusion Tails
3.4 Quantum Detectors
3.4.1 Photodetection in Semiconductors
3.4.2 Photodiodes and Their Relatives
3.4.3 Shunt Resistance
3.4.4 Speed
3.4.5 Stability
3.4.6 Photodiodes and Pulses
3.4.7 Phototransistors
3.4.8 Prepackaged Combinations of Photodiodes with Amplifiers and Digitizers
3.4.9 Split Detectors
3.4.10 Lateral Effect Cells
3.4.10.1 Applying Reverse Bias to Lateral‐Effect Cells
3.4.11 Position‐Sensing Detector Pathologies
3.4.12 Other Position Sensing Detectors
3.4.13 Infrared Photodiodes
3.4.14 Quantum Well‐Infrared Photodiodes
3.5 Photomultipliers
3.5.1 PMT Circuit Considerations
3.5.2 PMTs in Detail
3.5.3 Choosing a Photocathode Material
3.5.4 QE Improvement Tricks
3.5.4.1 How to Kill a PMT
3.5.5 Making Accurate PMT Measurements
3.5.5.1 Nonlinearity in Analog‐Mode PMTs
3.5.6 Avalanche Photodiodes (APDs)
3.5.7 APD Structure
3.5.8 Photon Counting with APDs
3.5.9 Multipixel Photon Counters
3.5.10 MPPCs and APDs vs. PMTs
3.5.10.1 MPPC Nonlinearity
3.5.11 Vacuum APDs
3.5.12 Photoconductors
3.6 Thermal Detectors
3.7 Image Intensifiers
3.7.1 Image Tubes
3.7.2 Microchannel Plates
3.7.3 Streak Tubes
3.8 Silicon Array Sensors
3.8.1 Charge‐Coupled Devices
3.8.2 Time Delay Integration (TDI) CCDs
3.8.3 Electron‐Multiplying CCDs
3.8.4 CMOS Imagers
3.8.5 Spatial Pattern Problems
3.8.6 Efficiency and Spectral Response
3.8.7 Correlated Double Sampling
3.8.8 Image Sensor Noise
3.8.9 Spatial Pattern
3.8.10 Linearity
3.8.11 Scientific CMOS Cameras
3.8.12 Charge Injection Devices (CIDs)
3.8.13 Photodiode Arrays
3.8.14 Video Cameras
3.8.15 Extending the Wavelength Range: CCDs + Fluors
3.8.16 Electron Storage Materials
3.8.17 Infrared Array Detectors
3.8.18 Intensified Cameras
3.8.19 Calibrating Image Sensors
3.8.20 Linearity Calibration
3.9 How Do I Know Which Noise Source Dominates?
3.9.1 Source Noise
3.9.2 Shot Noise
3.9.3 Background Fluctuations
3.9.4 Thermal Emission
3.9.5 Lattice Generation‐Recombination Noise
3.9.6 Multiplication Noise
3.9.7 Temperature Fluctuations
3.9.8 Electronic Noise
3.9.9 Noise Statistics
3.10 Hacks
3.10.1 Use an Optical Filter
3.10.2 Reduce the Field of View
3.10.3 Reduce the Detector Size
3.10.4 Tile with Detectors
3.10.5 Cool the Detector
3.10.6 Reduce the Duty Cycle
3.10.7 Use Coherent Detection
3.10.8 Catch the Front Surface Reflection
3.10.9 Watch Background Temperature
3.10.10 Form Linear Combinations
3.10.11 Use Solar Cells at AC
3.10.12 Make Windowed Photodiodes into Windowless Ones
3.10.13 Use a LED as a Photodetector
3.10.14 Use an Immersion Lens
3.10.15 Use a Non‐imaging Concentrator
3.10.16 Consider Fiber Bundles
3.10.17 Think Outside the Box
Chapter 4 Lenses, Prisms, and Mirrors
4.1 Introduction
4.2 Optical Materials
4.2.1 Glass
4.2.2 Temperature Coefficients of Optical Materials
4.2.3 Air and Other Gases
4.2.4 Optical Plastics
4.3 Light Transmission
4.3.1 UV Materials
4.3.2 IR Materials
4.4 Surface Quality
4.5 Windows
4.5.1 Leading Order Optical Effects
4.5.2 Optical Flats
4.6 Pathologies of Optical Elements
4.6.1 Birefringence
4.7 Fringes
4.7.1 Surface Reflections
4.7.2 Etalon Fringes
4.7.3 Getting Rid of Fringes
4.7.4 Smearing Fringes Out
4.7.5 Advice
4.8 Mirrors
4.8.1 Plate Beamsplitters
4.8.2 Non‐polarizing Beamsplitters
4.8.3 Pellicles
4.8.4 Flat Mirrors
4.9 Glass Prisms
4.9.1 Right Angle and Porro Prisms
4.9.2 Dove Prisms
4.9.3 Equilateral, Brewster, and Littrow Prisms
4.9.4 Pentaprisms
4.9.5 Other Constant‐Angle Prisms
4.9.6 Wedges
4.9.7 Roof Prisms
4.9.8 Corner Reflectors and Cats' Eyes
4.9.9 Beamsplitter Cubes
4.9.10 Fresnel Rhombs
4.10 Prism Pathologies
4.11 Lenses
4.11.1 Thin Lenses
4.11.2 Thick Lenses
4.11.3 Fast Lenses
4.11.4 Lens Bending
4.11.5 Dependence of Aberrations on Wavelength and Refractive Index
4.11.6 Aspheric Lenses
4.11.7 Cylinder Lenses
4.12 Complex Lenses
4.12.1 Achromats and Apochromats
4.12.2 Camera Lenses
4.12.3 Microscope Objectives
4.12.4 Infinity Correction
4.12.5 Focusing Mirrors
4.12.6 Anamorphic Systems
4.12.7 Fringe Diagrams
4.13 Other Lenslike Devices
4.13.1 GRIN Lenses
4.13.2 Diffractive Lenses and Holographic Optical Elements
4.13.3 Fresnel Lenses
4.13.4 Microlens Arrays
4.13.5 Axicons
Chapter 5 Coatings, Filters, and Surface Finishes
5.1 Introduction
5.1.1 Refraction and Reflection at an Interface
5.2 Metal Mirrors
5.2.1 Lossy Media
5.2.2 How Thick Does the Metal Have to Be?
5.2.3 Designing Metal Films
5.3 Transmissive Optical Coatings
5.3.1 Single Layer AR Coating
5.3.2 Dielectric Coating Materials
5.4 Simple Coating Theory
5.4.1 Multilayer Coating Theory
5.4.2 Lossless Coating Examples
5.4.3 Angle Tuning
5.4.4 Examples of Multilayer Coatings
5.4.5 Polarizing Beamsplitters
5.4.6 Holographic Polarizing Beamsplitters
5.4.7 Interference Filters
5.4.8 Coating Problems
5.4.9 Coating Plastics
5.5 Moth‐Eye Finishes
5.6 Absorptive Filters
5.6.1 Filter Glass
5.6.2 Internal and External Transmittance
5.6.3 Holographic Filters
5.6.4 Color Correcting Filters
5.7 Beam Dumps and Baffles
5.7.1 What Is a Black Surface?
5.7.2 Black Paint
5.7.3 India Ink
5.7.4 Black Anodizing
5.7.5 Dendritic Finishes
5.7.6 Black Appliques
5.7.7 Black Plastic
5.7.8 Black Wax
5.7.9 Black Glass
5.7.10 Designing Beam Dumps and Light Traps
5.7.11 Wood's Horn
5.7.12 Cone Dumps
5.7.13 Black Glass at Brewster's Angle
5.7.14 Shiny Baffles
5.7.15 Flat Black Baffles
5.7.16 Combinations
5.8 White Surfaces and Diffusers
5.8.1 Why Is It White?
5.8.2 Packed Powder Coatings
5.8.3 Barium Sulfate Paint
5.8.4 Spectralon
5.8.5 Opal Glass
5.8.6 Magic Invisible Tape
5.8.7 Integrating Spheres
5.8.8 Ping‐Pong Balls
5.8.9 Ground Glass
5.8.10 Holographic Diffusers
5.8.11 Microlens Arrays
5.8.12 Diffusers and Speckle
Chapter 6 Polarization
6.1 Introduction
6.2 Polarization of Light
6.2.1 Unpolarized Light
6.2.2 Highly Polarized Light
6.2.3 Circular Polarization
6.2.4 An Often‐Ignored Effect: The Pancharatnam–Berry Topological Phase
6.2.5 Orthogonal Polarizations
6.3 Interaction of Polarization with Materials
6.3.1 Polarizers
6.3.2 Birefringence
6.3.3 Retardation
6.3.4 Double Refraction
6.3.5 Walkoff
6.3.6 Optical Activity
6.3.7 Faraday Effect
6.3.8 Polarization and Lossy Coatings
6.4 Absorption Polarizers
6.4.1 Film Polarizers
6.4.2 Wire Grid Polarizers
6.4.3 Polarizing Glass
6.5 Brewster Polarizers
6.5.1 Pile‐of‐Plates Polarizers
6.5.2 Multilayer Polarizers
6.5.3 Polarizing Cubes
6.6 Birefringent Polarizers
6.6.1 Walkoff Plates
6.6.2 Savart Plates
6.7 Double‐Refraction Polarizers
6.7.1 Wollaston Prisms
6.7.2 Rochon Prisms
6.7.3 Cobbling Wollastons
6.7.4 Nomarski Wedges
6.7.5 Homemade Polarizing Prisms
6.8 TIR Polarizers
6.8.1 Refraction and Reflection at Birefringent Surfaces
6.8.2 Glan–Taylor
6.8.3 Glan–Thompson
6.9 Retarders
6.9.1 Wave Plates
6.9.2 Quarter Wave Plates
6.9.3 Half Wave Plates
6.9.4 Full Wave Plates
6.9.5 Multi‐order Wave Plates
6.9.6 ‘Zero‐Order’ Wave Plates
6.9.7 Film and Mica
6.9.8 Circular Polarizers
6.9.9 Subwavelength Grating Retarders
6.10 Polarization Control
6.10.1 Basis Sets for Fully Polarized Light
6.10.2 Partial Polarization and the Jones Matrix Calculus
6.10.3 Polarization States
6.10.4 Polarization Compensators
6.10.5 Circular Polarizing Film for Glare Control
6.10.6 Polarization Rotators
6.10.7 Depolarizers
6.10.8 Faraday Rotators and Optical Isolators
6.10.9 Beam Separators
6.10.10 Lossless Interferometers
6.10.11 Faraday Rotator Mirrors and Polarization Insensitivity
Chapter 7 Exotic Optical Components
7.1 Introduction
7.2 Gratings
7.2.1 Diffraction Orders
7.3 Grating Pathologies
7.3.1 Stray Light
7.3.2 Order Overlap
7.3.3 Ghosts
7.3.4 Mechanical Instability
7.3.5 Polarization Sensitivity
7.4 Types of Gratings
7.4.1 Reflection and Transmission Gratings
7.4.2 Ruled Gratings
7.4.3 Holographic Gratings
7.4.4 Concave Gratings
7.4.5 Echelles
7.5 Resolution of Grating Instruments
7.5.1 Spectral Selectivity and Slits
7.5.2 Angular Dispersion Factor
7.5.3 Diffraction Limit
7.5.4 Slit‐Limited Resolution
7.5.5 Étendue
7.6 Fine Points of Gratings
7.6.1 Order Strengths
7.6.2 Polarization Dependence
7.6.3 Bragg Gratings
7.7 Holographic Optical Elements
7.7.1 Combining Dispersing Elements
7.8 Photonic Crystals and Metamaterials
7.8.1 Photonic Crystals
7.8.2 Metamaterials
7.9 Retroreflective Materials
7.10 Scanners
7.10.1 Galvos
7.10.2 Rotating Scanners
7.10.3 Polygon Scanners
7.10.4 Polygon Drawbacks
7.10.5 Eliminating Scan Wobble
7.10.6 Software Raster Correction
7.10.7 Descanning
7.10.8 Constant Linear Scan Speed
7.10.9 Hologons
7.10.10 Fast and Cheap Scanners
7.10.11 Dispersive Scanning
7.10.12 Raster Scanning
7.10.13 Mechanical Scanning
7.11 Modulators
7.11.1 Pockels and Kerr Cells
7.11.2 House‐Trained Pockels Cells: Resonant and Transverse
7.11.3 Electro‐Optic Deflectors
7.11.4 Liquid Crystal
7.11.5 Acousto‐Optic Cells
7.11.6 Acousto‐Optic Tunable Filters
7.11.7 Acousto‐Optic Deflectors
7.11.8 Photoelastic Modulators
7.11.9 Acousto‐optic Laser Isolators
Chapter 8 Fiber Optics
8.1 Introduction
8.2 Fiber Characteristics
8.2.1 Fiber Virtues
8.2.2 Ideal Properties of Fiber
8.2.3 Fiber Vices
8.3 Fiber Theory
8.3.1 Modes
8.3.2 Degeneracy
8.3.3 Mode Coupling
8.3.4 Space‐Variant Coupling
8.3.5 Dispersion
8.3.6 Other Effects in Single Mode Fiber
8.4 Fiber Types
8.4.1 Single Mode Optical Fibers
8.4.2 Multimode Optical Fibers
8.4.2.1 Mode Spectrum and Loss
8.4.2.2 Multimode Fiber Étendue
8.4.3 Few‐Mode Fiber
8.4.4 Polarization‐Maintaining (PM) Fiber
8.4.5 Photonic‐Crystal Fiber
8.4.6 Chalcogenide Fibers for IR Power Transmission
8.4.7 Fiber Bundles and Étendue Management
8.4.8 Split Bundles
8.4.9 Coupling into Bundles
8.4.10 Liquid Light Guides
8.5 Other Fiber Properties
8.5.1 Leaky Modes
8.5.2 Cladding Modes
8.5.3 Bending
8.5.4 Bending and Mandrel Wrapping
8.5.5 Bend Birefringence and Polarization Compensators
8.5.6 Piezo‐optical Effect and Pressure Birefringence
8.5.7 Twisting and Optical Activity
8.5.8 Fiber Loss Mechanisms
8.5.9 Mechanical Properties
8.5.10 Fabry–Perot Effects
8.5.11 Strain Effects
8.5.12 Temperature Coefficients
8.5.13 Bad Company: Fibers and Laser Noise
8.5.14 Fiber Dispersion and FM Noise
8.6 Working with Fibers
8.6.1 Getting Light In and Out
8.6.2 Launching Into Fibers in the Lab
8.6.3 Waveguide‐to‐Waveguide Coupling
8.6.4 Connecting Single‐Mode to Multimode Fiber
8.6.5 Fibers and Pulses
8.6.6 Mounting Fibers in Instruments
8.6.7 Connectors
8.6.8 Splices
8.6.9 Expanded‐Beam Connectors
8.6.10 Cleaving Fibers
8.7 Fiber Devices
8.7.1 Fiber Couplers
8.7.2 Fiber Gratings
8.7.3 Type II Gratings
8.7.4 Fiber Amplifiers
8.7.5 Fiber Lasers
8.7.6 Fiber Polarizers
8.7.7 Modulators
8.7.8 Switches
8.7.9 Isolators
8.8 Diode Lasers and Fiber Optics
8.9 Fiber Optic Sensors
8.9.1 Sensitivity
8.9.2 Stabilization Strategy
8.9.3 Handling Excess Noise
8.9.4 Source Drift
8.10 Intensity Sensors
8.10.1 Microbend Sensors
8.10.2 Fiber Pyrometers
8.10.3 Fluorescence Sensors
8.10.4 Optical Time‐Domain Reflectometry
8.11 Spectrally Encoded Sensors
8.11.1 Fiber Bragg Grating Sensors
8.11.2 Extrinsic Fabry–Perot Sensors
8.11.3 Other Strain Sensors
8.11.4 Fiber Bundle Spectrometers
8.11.5 Raman Thermometers
8.11.6 Band Edge Shift
8.11.7 Colorimetric Sensors
8.12 Polarimetric Sensors
8.12.1 Faraday Effect Ammeters
8.12.2 Birefringent Fiber
8.12.3 Photonic Crystal Fiber Sensors
8.13 Fiber Interferometers
8.13.1 Single Mode Interferometers
8.13.2 Two‐Mode Interferometers
8.14 Two‐Beam Fiber Interferometers
8.14.1 Mach–Zehnder
8.14.2 Michelson
8.14.3 Sagnac
8.15 Multiple Beam Fiber Interferometers
8.15.1 Fabry–Perot
8.15.2 Ring Resonator
8.15.3 Motion Sensors
8.15.4 Coherence‐Domain Techniques
8.16 Phase and Polarization Stabilization
8.16.1 Passive Interrogation
8.16.2 Frequency Modulation
8.16.3 Fringe Surfing
8.16.4 Broadband Light
8.16.5 Ratiometric Operation
8.16.6 Polarization‐Insensitive Sensors
8.16.7 Polarization Diversity
8.16.8 Temperature Compensation
8.16.9 Annealing
8.17 Multiplexing and Smart Structures
8.18 Fiber Sensor Hype
Chapter 9 Optical Systems
9.1 Introduction
9.2 What, Exactly, Does a Lens Do?
9.2.1 Ray Optics
9.2.2 Connecting Rays and Waves: Wavefronts
9.2.3 Rays and the Eikonal Equation
9.2.4 Geometric Optics and Electromagnetism
9.2.5 Variational Principles in Ray Optics
9.2.6 Schlieren Effect
9.2.7 The Geometrical Theory of Diffraction
9.2.8 Pupils
9.2.9 Invariants
9.2.10 The Abbe Sine Condition
9.2.11 Optical Systems Nomenclature
9.3 Diffraction
9.3.1 Plane Wave Representation
9.3.2 Green's Functions and Diffraction
9.3.3 The Kirchhoff Approximation
9.3.4 Plane Wave Spectrum of Diffracted Light
9.3.5 Diffraction at High NA
9.3.6 Propagating from a Pupil to an Image
9.3.7 Telecentricity
9.3.8 Stereoscopy
9.3.9 The Importance of the Pupil Function
9.3.10 Coherent Transfer Functions
9.3.11 Optical Transfer Functions
9.3.12 Shortcomings of the OTF Concept
9.3.13 Modulation Transfer Function
9.3.14 Cascading Optical Systems
9.3.15 Which Transfer Function Should I Use?
9.4 Aberrations
9.4.1 Aberration Nomenclature
9.4.2 Aberrations of Windows
9.4.3 Broken Symmetry and Oblique Aberrations
9.4.4 Dependence on Stop Position
9.5 Representing Aberrations
9.5.1 Seidel Aberrations
9.5.2 Aberrations of Beams
9.5.3 Chromatic Aberrations
9.5.4 Strehl Ratio
9.6 Optical Design Advice
9.6.1 Keep Your Eye on the Final Output
9.6.2 Combining Aberration Contributions
9.7 Practical Applications
9.7.1 Spatial Filtering – How and Why
9.7.2 How to Clean Up Beams
9.7.3 Dust Doughnuts
9.8 Illuminators
9.8.1 Flying‐Spot Systems
9.8.2 Direction Cosine Space
9.8.3 Bright and Dark Field
9.8.4 Flashlight Illumination
9.8.5 Critical Illumination
9.8.6 Köhler Illumination
9.8.7 Testing Illuminators
9.8.8 Image Radiance Uniformity
9.8.9 Contrast and Illumination
9.8.10 Retroreflectors and Illumination
Chapter 10 Optical Measurements
10.1 Introduction
10.2 Grass on the Empire State Building
10.2.1 Background, Noise, and Spurious Signals
10.2.2 Pedestal
10.2.3 Background Fluctuations
10.2.4 Noise Statistics
10.2.5 Laser Noise
10.2.6 Lamp Noise
10.2.7 Media Noise
10.2.8 Electrical Interference
10.2.9 Electronic Noise
10.2.10 Quantization Noise
10.2.11 Baseband Isn't a Great Neighborhood
10.3 Detection Issues: When Exactly Is Background Bad?
10.3.1 Dark Field
10.3.2 Bright Field: Amplitude vs. Intensity Sensitivity
10.3.3 Coherent Background
10.3.4 Optical Theorem
10.3.5 Dim Field Measurements
10.3.6 Bright and Dark Field are Equivalent
10.3.7 Heterodyne Interferometry
10.3.8 SSB Interferometers
10.3.9 Shot‐Noise Limited Measurements at Baseband
10.4 Measure the Right Thing
10.4.1 Phase Measurements
10.4.2 Multiple‐Scale Measurements Extend Dynamic Range
10.4.3 Fringes
10.5 Getting More Signal Photons
10.5.1 Don't Throw Photons Away
10.5.2 Optimize the Geometry
10.5.3 Use Laser Scanning Measurements
10.5.4 Modify the Sample
10.5.5 Corral Those Photons
10.6 Reducing the Background Fluctuations
10.6.1 Beam Pointing Stabilization
10.6.2 Beam Intensity Stabilization
10.6.3 Photocurrent Stabilization
10.6.4 Ratiometric Measurements
10.6.5 Changing the Physics
10.7 Optically Zero‐Background Measurements
10.7.1 Dark Field
10.7.2 Fringe‐based Devices
10.8 Spectrally Resolved Measurements
10.8.1 LEDs and Filters
10.8.2 Grating Spectroscopy
10.8.2.1 OMA Spectroscopy
10.8.2.2 Slitless Spectroscopy
10.8.3 Fourier Transform Infrared (FTIR) Spectroscopy
10.8.4 Fluorescence and Photon Counting
10.8.5 Nonlinear and Bilinear Measurements
10.8.6 Non‐Optical Detection
10.8.7 Active Fringe Surfing
10.8.8 Polarization Tricks
10.8.9 Optical Time Gating
10.9 Electronically Zero‐Background Measurements
10.9.1 Polarization Flopping
10.9.2 Electronic Time Gating
10.9.3 Nulling Measurements
10.9.4 Differential Measurements
10.9.5 Other Linear Combinations
10.9.6 Laser Noise Cancellers
10.10 Labeling Signal Photons
10.10.1 Chopping
10.10.2 Scanning
10.10.3 AC Measurements
10.10.4 Modulation Mixing
10.10.5 AC Interference
10.10.6 Labeling Modulation Phase
10.10.7 Labeling Arrival Time
10.10.8 Labeling Time Dependence
10.10.9 Labeling Wavelength
10.10.10 Labeling Coherence
10.10.11 Labeling Coincidence
10.10.12 Labeling Position
10.10.13 Labeling Polarization
10.11 Closure
Chapter 11 Designing Electro‐Optical Systems
11.1 Introduction
11.2 Do You Really Want To Do This?
11.2.1 Collegiality
11.2.2 Collegiality and Team Productivity
11.2.3 Choosing Projects
11.2.4 Procedural Advice
11.2.4.1 Take Play Seriously
11.2.4.2 Design Standing Up
11.2.4.3 Take Counsel of the Devil
11.2.4.4 Resist Over‐Promising
11.2.4.5 Keep Some Margin in Your Back Pocket
11.2.4.6 Have People to Cover Your Back
11.2.4.7 Confess When Your Project Is on the Skids
11.2.4.8 Define What Constitutes Success
11.2.4.9 Know Your Organization
11.2.4.10 Understand Your Position
11.2.4.11 Become a Wizard
11.2.4.12 Don't Build a Pyramid
11.2.4.13 Understand the Pecking Order
11.2.4.14 Don't Fight “Good Enough”
11.2.4.15 Achieve Agreement on Specifications Before Starting
11.2.4.16 Show Some Hustle
11.2.4.17 Watch Out for Liability
11.2.4.18 Pssst…Just Between You and Me: Sometimes the Naysayers Are Right
11.3 Very Basic Marketing
11.3.1 Who Or What Is Your Customer?
11.3.2 Making A Business Case: Internal
11.3.3 Making A Business Case: External
11.3.4 Don't Destroy the Market
11.3.5 Budget for Market Creation
11.3.6 Budget for After‐Sales Support
11.4 Classes of Measurement
11.4.1 Know Your Measurement Physics
11.4.2 Crunchy Measurements
11.4.3 In‐Between Measurements
11.4.4 Squishy Measurements
11.4.5 Pretty Pictures
11.4.6 Pretty‐Pictures Measurements
11.5 Technical Taste
11.5.1 Know What Your System Should Look Like
11.5.1.1 Don't Measure Anything You Don't Care About
11.5.1.2 Avoid Obese Digital Processing
11.5.1.3 Have a Fallback Position
11.5.1.4 Design Defensively
11.5.1.5 Avoid Underengineered Complexity
11.5.1.6 Know When It's Time for a Clean Sheet of Paper
11.5.1.7 Beware of Signal Processing Fads
11.5.1.8 Beware of Optical Fads
11.6 Instrument Design
11.6.1 Where to Begin
11.6.1.1 Know the Problem
11.6.1.2 Mess Around With the Tools
11.6.1.3 Understand the Sources of SNR Limitations
11.6.1.4 Look for other constraints
11.6.1.5 Write a Specification
11.6.1.6 Include All Relevant Parameters
11.6.1.7 Solve Stupid Problems by Overkill
11.6.1.8 Make Tradeoffs Early
11.6.1.9 Identify Show‐Stoppers Early
11.6.1.10 Do Your Tool‐Building Early
11.6.1.11 Know What Limits You're Pushing and Why
11.6.1.12 Use Standard Parts
11.6.1.13 Make Good Drawings
11.6.1.14 It Isn't Finished Until the Test Stand's Done
11.7 Guiding Principles
11.7.1 Design Strategy
11.7.1.1 Trust Freshman Physics
11.7.1.2 Believe Your Photon Budget
11.7.1.3 Reduce the Background
11.7.1.4 Don't Yearn for Greener Pastures
11.7.1.5 Model It
11.7.1.6 Get Ground Truth
11.7.1.7 Keep It Simple
11.7.1.8 Move the Goal Posts
11.7.1.9 Always Try It “the Other Way Round”
11.7.1.10 Build the Test Fixture Into the Instrument
11.7.1.11 Keep Gross Errors Obvious
11.7.1.12 Stability Is Even More Important Than SNR
11.8 Design for Alignment
11.8.1 Alignment Hygiene
11.8.1.1 Use Corner Cube Interferometers
11.8.1.2 Allow Some Slop
11.8.1.3 Use the Poor Man's Corner Cube: Retroreflective Tape
11.8.1.4 Put in a Viewer – You Can't Align What You Can't See
11.8.1.5 Use Verniers
11.8.1.6 Adjust the Right Thing
11.8.1.7 Watch Out for Temperature Gradients
11.8.1.8 Usually Follow the Leader
11.8.1.9 Don't Always Follow the Leader
11.9 Turning a Prototype into a Product
11.9.1 Be Very Careful of “Minor” Optical Design Changes
11.9.2 Don't Design in Etalon Fringes
11.9.3 Demos
11.9.3.1 The Story
11.9.3.2 The Demo
11.9.4 Handle Demo Karma Gracefully
Chapter 12 Building Optical Systems
12.1 Introduction
12.2 Construction Style
12.3 Build What You Designed
12.3.1 Trust But Verify
12.4 Assembling Lab Systems
12.4.1 Build Horizontally
12.4.2 Use Metal
12.4.3 Scribble on the Optical Table
12.4.4 Mounts
12.4.5 Use Microbench for Complicated Systems
12.4.6 Machine a Base Plate
12.4.7 Use Irises
12.4.8 Getting The Right Height
12.4.9 Light‐Tightness
12.4.10 Chop Up 35 mm SLR Cameras
12.4.11 Try To Use At Least One Screw Per Component
12.4.12 The Poor Man's Machine Shop: JB Weld Putty
12.4.13 Detector Alignment Needs Thought
12.4.14 Do‐It‐Yourself Spatial Filters
12.4.15 Field Lenses
12.4.16 Things to Count On
12.4.17 Clamping
12.4.18 Soft Lenses
12.4.19 Dimensional Stability
12.4.20 Too Much of a Good Thing: Hard Epoxy
12.4.21 Beam Quality
12.4.22 Siegman's M2 Beam Propagation Factor
12.4.23 Image Quality
12.5 Optical Assembly and Alignment Philosophy
12.5.1 Stability
12.5.2 Orthogonality
12.5.3 Use Serendipitous Information
12.6 Collimating Beams
12.6.1 Direct Collimation
12.6.2 Fizeau Wedges
12.6.3 Shear Plates
12.6.4 Collimeter
12.7 Focusing
12.7.1 Autocollimation
12.7.2 Direct Viewing
12.7.3 Foucault Knife Edge
12.7.4 Intensity‐Based Chopping Tests
12.7.5 Diffraction Focusing
12.7.6 Diffraction Interferometry
12.7.7 Speckle Focusing
12.7.8 Focusing Imagers
12.7.9 Standards
12.7.10 Sub‐apertures
12.8 Alignment and Testing
12.9 Prototypes
12.9.1 Cage Systems
12.9.2 Optical Tables
12.10 Aligning Beams with Other Beams
12.10.1 Co‐Propagating Beams
12.10.2 Constrained Beam‐to‐Beam Alignment
12.10.3 Counterpropagating Beams
12.11 Advanced Tweaking
12.11.1 Interferometers and Back‐Reflections
12.11.2 Collinearity
12.11.3 Backlash and Stick‐Slip
12.11.4 Adding Verniers
12.11.5 Cavities With Obstructions
12.11.6 Aligning Two‐Beam Interferometers
12.11.7 Aligning Heterodyne Interferometers
12.11.8 Measuring Focal Lengths
12.11.9 Aligning Fabry–Perot Interferometers
12.11.10 Aligning Lasers
12.11.11 Aligning Spatial Filters
12.11.12 Use Corner Cubes and Pentaprisms
12.11.13 Use Quad Cells For XY Alignment
12.11.14 Use Fringes for Angular Alignment
12.12 Aligning Laser Systems
12.12.1 Define an Axis
12.12.2 Adding Elements
12.12.3 Marking Lens Elements
12.12.4 Lenses Are Easier Than Mirrors, Especially Off‐Axis Aspheres
12.12.5 Use an Oscilloscope
12.13 Adhesives
12.13.1 Structural Adhesives
12.13.2 Optical Adhesives: UV Epoxy
12.13.3 Optical Contacting
12.13.4 Hydroxyl Bonding
12.13.5 Frit Bonding and “Glass Solder”
12.13.6 Temporary Joints: Index Oil and Wax
12.14 Cleaning
12.14.1 What Does a Clean Lens Look Like?
12.14.2 When to Clean
12.14.3 Cleaning Lenses
12.14.4 Cleaning Gratings
12.14.5 Peel‐Off Cleaning Coatings: Collodion
12.15 Environmental Considerations
12.15.1 Fungus
12.15.2 Coating Drift
12.15.3 Lens Staining
12.15.4 Drift From Temperature and Humidity
Chapter 13 Signal Processing
13.1 Introduction
13.2 Analog Signal Processing Theory
13.2.1 Two Port Black Box
13.2.2 Linearity and Superposition
13.2.3 Time Invariance
13.2.4 Fourier Space Representation
13.2.5 Analytic Signals
13.3 Modulation and Demodulation
13.3.1 Terms
13.3.2 Phasors
13.3.3 Frequency Mixing
13.3.4 Amplitude Modulation (AM)
13.3.5 Double Sideband (DSB)
13.3.6 Single Sideband (SSB)
13.3.7 Phase Modulation (PM)
13.3.8 Frequency Modulation (FM)
13.4 Amplifiers
13.5 Departures From Linearity
13.5.1 Harmonics
13.5.2 Frequency Multipliers
13.5.3 Intermodulation
13.5.4 Saturation
13.5.5 Gain Plans
13.5.6 Cross‐Modulation
13.5.7 AM–PM conversion
13.5.8 Distortion in Angle‐Modulated Systems
13.5.9 Keeping Spurs Under Control
13.6 Noise and Interference
13.6.1 White Noise and 1/f Noise
13.6.2 Popcorn Noise
13.6.3 Johnson (Thermal) Noise
13.6.4 Shot Noise in Circuits
13.6.5 Other Circuit Noise
13.6.6 Noise Figure, Noise Temperature, and All That
13.6.7 Noise Models of Amplifiers
13.6.8 Noise Bandwidth
13.6.9 Measuring Noise
13.6.10 Combining Noise Contributions
13.6.11 Noise of Cascaded Stages
13.6.12 Interference: What Does a Spur Do To My Measurement, Anyway?
13.6.13 AM Noise and PM Noise
13.6.14 Additive vs. Multiplicative Noise
13.6.15 Oscillator Noise Spectra
13.6.15.1 Laser Noise
13.6.16 Noise Statistics
13.6.17 Gaussian Statistics
13.6.18 Shot Noise Statistics
13.6.19 Thresholding
13.6.20 Photon Counting Detection
13.7 Frequency Conversion
13.7.1 Mixers
13.7.2 Choosing an IF
13.7.3 Image Rejection
13.7.4 High Side vs. Low Side LO
13.7.5 Direct Conversion
13.7.6 Effects of LO Noise
13.7.7 Gain Distribution
13.7.8 Software‐Defined Radio
13.8 Filtering
13.8.1 Cascading Filters
13.8.2 Impulse Response
13.8.3 Step Response
13.8.4 Causality
13.8.5 Filter Design
13.8.6 Group Delay
13.8.7 Hilbert Transform Filters
13.8.8 Linear Phase Bandpass and Highpass Filters
13.8.9 How to Choose a Filter
13.8.10 Matched Filtering and Pulses
13.8.11 Pulsed Measurements and Shot Noise
13.8.12 Pulsed Measurements and Correlated Double Sampling
13.9 Signal Detection
13.9.1 Phase Sensitive Detectors
13.9.2 AM Detectors
13.9.3 PLL Detectors
13.9.4 FM/PM Detectors
13.9.5 Phase‐Locked Loops
13.9.6 I and Q Detection
13.9.7 Pulse Detection
13.10 Reducing Interference and Noise
13.10.1 Lock‐In Amplifiers
13.10.2 Filter Banks
13.10.3 Synchronization
13.10.4 Time‐Gated Detection
13.10.5 Signal Averaging
13.10.6 Frequency Tracking
13.10.7 Modulation‐Mixing Measurements
13.11 Data Acquisition and Control
13.11.1 Quantization
13.11.2 Choosing A Sampling Strategy
13.11.3 Designing with ADCs
13.11.4 Choosing the Resolution
13.11.5 Keep Zero On‐Scale
Chapter 14 Electronic Building Blocks
14.1 Introduction
14.2 Resistors
14.2.1 Resistor Arrays
14.2.2 Potentiometers
14.2.3 Trim Pots
14.2.4 Loaded Pots
14.3 Capacitors
14.3.1 Ceramic and Plastic Film Capacitors
14.3.2 Surface Mount Film Capacitors
14.3.3 Parasitic Inductance and Resistance
14.3.4 Dielectric Absorption
14.3.5 Electrolytic Capacitors
14.3.6 Variable Capacitors
14.3.7 Varactor Diodes
14.3.8 Inductors
14.3.9 High Frequency Inductors
14.3.10 Variable Inductors
14.3.11 Resonance
14.3.12 L‐Networks and Q
14.3.13 Inductive Coupling
14.3.14 Loss In Resonant Circuits
14.3.15 Temperature Compensating Resonances
14.3.16 Transformers
14.3.17 Tank Circuits
14.4 Transmission Lines
14.4.1 Mismatch and Reflections
14.4.2 Quarter‐Wave Series Sections
14.4.3 Coaxial Cable
14.4.4 Balanced Lines
14.4.5 Twisted Pair
14.4.6 Microstrip
14.4.7 Termination Strategies
14.5 Transmission Line Devices
14.5.1 Attenuators
14.5.2 Shunt Stubs
14.5.3 Trombone Lines
14.5.4 Transmission Line Transformers and Chokes
14.5.5 Directional Couplers
14.5.6 Splitters and Tees
14.6 Diodes
14.6.1 Diode Switches
14.7 Bipolar Junction Transistors
14.7.1 Temperature Dependence of IS and VBE
14.7.2 Speed
14.7.3 Bias Stability
14.7.4 Negative Feedback
14.7.5 Miller Effect
14.7.6 Cutoff and Saturation
14.7.7 Inverted Transistors
14.7.8 Amplifier Configurations
14.7.9 Differential Pairs
14.7.10 Cascode Amplifiers
14.7.11 Silicon Germanium BJTs
14.7.12 Current‐Mode Circuitry
14.8 Field‐Effect Transistors (FETs)
14.8.1 Junction FETs
14.9 Heterojunction FETs
14.9.1 Cascoding pHEMTs
14.10 Signal Processing Components
14.10.1 Choosing Components
14.10.2 Read the Data Sheet Carefully
14.10.3 Don't Trust Typical Specs
14.10.4 Watch for Gotchas
14.10.5 Specsmanship
14.10.5.1 Dishonest Specsmanship
14.10.6 Mixers
14.10.7 LO Effects
14.10.8 Mixers and Impedance Matching
14.10.9 Op Amps
14.10.10 Differential Amps
14.10.11 RF Amps
14.10.12 Isolation Amps
14.10.13 Radio ICs
14.10.14 Stability
14.10.15 Slew Rate
14.10.16 Settling Time
14.10.17 Limiting Amplifiers
14.10.18 Lock‐In Amplifiers
14.11 Digitizers
14.11.1 Voltage References
14.11.2 Digital‐to‐Analog Converters
14.11.3 Delta‐Sigma Modulators
14.11.4 Track/Hold amplifiers
14.11.5 Analog‐To‐Digital Converters
14.11.6 DAC and ADC Pathologies
14.11.7 Differential Nonlinearity And Histograms
14.11.8 Dynamic Errors
14.11.9 Dynamic Range
14.11.10 ADC Noise
14.11.11 Ultrafast ADCs
14.12 Analog Behavior of Digital Circuits
14.12.1 Frequency Dividers
14.12.2 Phase Noise and Jitter of Logic
14.12.3 Analog Uses of Gates and Inverters
Chapter 15 Electronic Subsystem Design
15.1 Introduction
15.2 Design Approaches
15.2.1 Describe the Problem Carefully
15.2.2 Systems Engineers and Thermodynamics
15.2.3 Guess a Block Diagram
15.2.4 Getting the Gains Right
15.2.5 Error Budget
15.2.6 Lab Systems and Proof‐of‐Concept Protos
15.2.7 Interface Design
15.3 Perfection
15.3.1 Flying Capacitors Can Add and Subtract Perfectly
15.3.2 Independent Noise Sources Are Really Uncorrelated
15.4 Feedback Loops
15.4.1 Feedback Amplifier Theory and Frequency Compensation
15.4.2 Loop Gain
15.4.3 Adding Poles and Zeroes
15.4.4 Integrating Loops
15.4.5 Settling and Windup
15.4.6 Speedup Tricks
15.4.7 Output Loading
15.5 Local Feedback
15.6 Signal Detectors
15.6.1 AM Detection
15.6.2 Emitter Detector
15.6.3 Synchronous Detectors
15.6.4 High Performance Envelope Detection
15.6.5 Pulse Detection
15.6.6 Gated Integrators
15.6.7 Two‐Diode Line Triggers
15.6.8 Peak Track/Hold
15.6.9 Perfect Rectifiers
15.6.10 Logarithmic Detectors
15.6.11 Phase Sensitive Detectors
15.6.12 FM Detectors
15.6.13 Delay Discriminator
15.7 Phase‐Locked Loops
15.7.1 PLL Lock Acquisition
15.7.2 Loop Design
15.7.3 More Complicated PLLs
15.7.4 Noise in PLLs
15.7.5 Lock Detection
15.7.6 Acquisition Aids
15.8 Calibration
15.8.1 Calibrating Phase Detectors
15.8.2 Calibrating Amplitude Detectors
15.8.3 Calibrating a Limiter
15.9 Filters
15.9.1 LC Filters
15.9.2 Butterworth Filters
15.9.3 Chebyshev Filters
15.9.4 Filters With Good Group Delay
15.9.5 Filters With Good Skirts
15.9.6 Lowpass to Bandpass Transformation
15.9.7 Tuned Amplifiers
15.9.8 Use Diplexers to Control Reflections and Instability
15.9.9 Belleman Absorptive Filters
15.10 Other Stuff
15.10.1 CW Diode Laser Controllers
15.10.2 Pulsed Diode Laser Controllers
15.10.3 Digitizing Other Stuff
15.10.4 Use Sleazy Approximations and Circuit Hacks
15.10.5 Oscillators
15.11 More Advanced Feedback Techniques
15.11.1 Put the Nonlinearity in the Loop
15.11.2 Feedback Nulling
15.11.3 Auto‐zeroing
15.11.4 Automatic Gain Control
15.11.5 Automatic Level Control
15.11.6 Feedback Loops Don't Have to Go to DC
15.12 Hints
15.12.1 Invert When Possible
15.12.2 Watch for Startup Problems
15.12.3 Subtract, Don't Divide
15.13 Linearizing
15.13.1 Balanced Circuits
15.13.2 Off‐Stage Resonance
15.13.3 Waveform Control
15.13.4 Breakpoint Amplifiers
15.13.5 Feedback Using Matched Nonlinearities
15.13.6 Inverting a Linear Control
15.13.7 Feedforward
15.13.8 Predistortion and Preemphasis
15.14 Ultrastable Low Frequency Circuits
15.15 Digital Control and Communication
15.15.1 Multiple Serial DACS and Digital Pots
15.15.2 Data Acquisition Bricks
15.15.2.1 Nonsimultaneous Sampling
15.15.2.2 Simultaneous Control and Acquisition
15.15.3 Doing Better Data Acq in the Lab
15.15.4 Programmable Logic
15.16 Miscellaneous Tricks
15.16.1 Avalanche Transistors
15.17 Bulletproofing
15.17.1 Hangup States
15.17.2 Hot Plugging
15.17.3 Short‐Circuit Protection
15.17.4 Series Current Limiters
15.17.5 Transient Overvoltage Protection
15.17.6 Continuous Overvoltage Protection
15.17.7 Thermal Fault Protection
15.18 Interference
15.18.1 Switching Power Supply Problems
15.19 Reliable Designs
15.19.1 It Works Once, How Do I Make It Work Many Times?
15.19.2 Center Your Design
Chapter 16 Electronic Construction Techniques
16.1 Introduction
16.2 Circuit Strays
16.3 Circuit Boards
16.3.1 Microstrip Line
16.3.2 Inductance and Capacitance of Traces
16.3.3 Stray Inductance
16.3.4 Stray Capacitance
16.3.5 Measuring Capacitance
16.4 Stray Coupling
16.4.1 Capacitive Coupling
16.4.2 Transmission Line Coupling
16.4.3 Telling Them Apart
16.5 Ground Plane Construction
16.5.1 Ground Currents
16.5.2 Ground Planes
16.5.3 Relieving the Ground Plane
16.5.4 Skin Depth
16.5.5 Shielding Effectiveness and the Large Box Effect
16.6 Technical Noise and Interference
16.6.1 What Is Ground, Anyway?
16.6.2 Ground Loops
16.6.3 Floating Transducers
16.6.4 Mixed Signal Boards
16.6.5 High‐Impedance Nodes and Layout
16.6.6 High‐Density Interconnects and Interference
16.6.7 Connecting Coaxial Cables
16.6.8 Bypassing and Ground/Supply Inductance
16.6.9 Bypass Capacitor Self‐Resonances
16.6.10 Decoupling Analog Circuits
16.7 Product Construction
16.7.1 Cost vs. Performance
16.7.2 Chassis Grounds
16.7.3 PC Boards
16.7.4 Design for Test
16.7.5 Connectors and Switches
16.7.6 Multi‐Card Systems
16.8 Getting Ready
16.8.1 Buy a Stock of Parts
16.8.2 Get the Right Equipment
16.8.3 Soldering
16.8.4 Cleaning
16.9 Prototyping
16.9.1 Dead Bug Method
16.9.2 SPICE Simulations
16.9.3 When to Prototype
16.9.4 Laying Out the Prototype
16.9.5 Adding Components
16.9.6 Hookup Wire
16.9.7 Wire It Correctly and Check It
16.9.8 Cobbling Copper Clad Board
16.9.9 Perforated Board
16.9.10 Perf Board with Pads
16.9.11 White Solderless Breadboards
16.9.12 Prototype Printed Circuit Boards
16.9.13 Blowing Up Prototypes
16.10 Surface Mount Prototypes
16.10.1 Quick‐Turn PC Boards
16.10.2 Stuffing Surface Mount PC Boards
16.10.3 Reflow Soldering
16.10.4 Debugging SMT Boards
16.10.5 Probe Stations
16.10.6 Hacking SMTs
16.10.7 Board Leakage
16.11 Prototyping Filters
16.11.1 Standard Capacitors
16.11.2 Calibrating Inductors and Capacitors: A Hack
16.11.3 Filter Layout
16.11.4 Watch for Inductive Coupling
16.12 Tuning, or, You Can't Hit What You Can't See
Chapter 17 Digital Signal Processing
17.1 Introduction
17.2 Elementary Operations
17.2.1 Gain and Offset
17.2.2 Background Correction and Calibration
17.2.3 Frame Subtraction
17.2.4 Baseline Restoration
17.2.5 Two Channel Correction
17.2.6 Plane Subtraction and Drift
17.2.7 More Aggressive Drift Correction
17.3 Dead Time Correction
17.4 Fourier Domain Techniques
17.4.1 Discrete Function Spaces
17.4.2 Finite Length Data
17.4.3 Sampled Data Systems
17.4.4 The Sampling Theorem and Aliasing
17.4.5 Discrete Convolution
17.4.6 Fourier Series Theorems
17.4.7 The Discrete Fourier Transform
17.5 The Fast Fourier Transform
17.5.1 Does the DFT Give the Right Answer?
17.5.2 Leakage and Data Windowing
17.5.3 Data Windowing
17.5.4 Interpolation of Spectra
17.6 Power Spectrum Estimation
17.6.1 DFT Power Spectrum Estimation: Periodograms
17.6.2 Maximum Entropy (All Poles) Method
17.7 Digital Filtering
17.7.1 Circular Convolution
17.7.2 Windowed Filter Design
17.7.3 Z Transforms
17.7.4 Filtering in the Frequency Domain
17.7.5 Optimal Filter Design
17.8 Deconvolution
17.8.1 Inverse Filters
17.8.2 Wiener Filters
17.9 Resampling
17.9.1 Decimation
17.10 Fixing Space‐Variant Instrument Functions
17.11 Finite Precision Effects
17.11.1 Quantization
17.11.2 Roundoff
17.11.3 Overflow
17.12 Pulling Data Out of Noise
17.12.1 Shannon's Theorem
17.12.2 Model Dependence
17.12.3 Correlation Techniques
17.12.4 Numerical Experiments
17.12.5 Signal Averaging
17.12.6 Two‐Point Correlation
17.13 Phase Recovery Techniques
17.13.1 Unwrapping
17.13.2 Unwrapping in 2D
17.13.3 Phase Shifting Measurements
17.13.4 Fienup's Algorithm
Chapter 18 Front Ends
18.1 Introduction
18.1.1 Noise Sources
18.1.2 Sanity Checking
18.2 Photodiode Front Ends
18.2.1 The Simplest Front End: A Resistor
18.2.2 Reducing the Load Resistance
18.3 Key Idea: Reduce the Swing Across Cd
18.4 Transimpedance Amplifiers
18.4.1 Frequency Compensation compensation
18.4.2 Noise in the Transimpedance Amp
18.4.3 Choosing the Right Op Amp
18.5 External Input Stages
18.5.1 FET Figures of Merit
18.5.2 No Such Amp Exists: Cascode Transimpedance Amplifiers
18.5.3 Noise in the Cascode
18.5.4 Externally Biased Cascode
18.5.5 Noise Considerations
18.5.6 Bootstrapping the Cascode
18.5.7 Circuit Considerations
18.5.8 One Small Problem … Obsolete Parts
18.5.9 Improved Bootstraps
18.5.10 Power Supply Noise
18.5.11 Capacitive Pickup
18.5.12 Beyond Transimpedance Amps: Cascode + Noninverting Buffer
18.5.13 Choosing Transistors
18.5.14 Nanoamps and Picoamps
18.6 How to Go Faster
18.6.1 Series Peaking
18.6.2 Broader Band Networks
18.6.3 Matching Networks and Bode's Theorem
18.6.4 T‐Coils
18.7 Advanced Photodiode Front Ends
18.7.1 Linear Combinations
18.7.2 Analog Dividers
18.7.3 Noise Cancellers
18.7.4 Using Noise Cancellers
18.7.5 Noise Canceller Performance
18.7.6 Multiplicative Noise Rejection
18.7.7 Applications
18.7.8 Limitations
18.8 Other Types of Front End
18.8.1 Low Level Photodiode Amplifiers
18.8.2 Pyroelectric Front Ends
18.8.3 IR Photodiode Front Ends
18.8.4 Transformer Coupling
18.9 Hints
Chapter 19 Bringing Up the System
19.1 Introduction
19.1.1 The Particle Counter That Wouldn't
19.2 Avoiding Catastrophe
19.2.1 Incremental Development
19.2.2 Greedy Optimization
19.2.3 Specifying the Interfaces
19.2.4 Talking to Each Other
19.2.5 Rigorous Subsystem Tests
19.2.6 Plan the Integration Phase Early
19.2.7 Don't Ship It Till It's Ready
19.3 Debugging and Troubleshooting
19.4 Getting Ready
19.5 Indispensable Equipment
19.5.1 Oscilloscopes
19.5.2 Sampling Scopes
19.5.3 Spectrum Analyzers
19.5.4 Probes
19.6 Debugging Pickup and Interference Problems
19.6.1 Test Setups
19.7 Digital Troubleshooting
19.8 Analog Electronic Troubleshooting
19.9 Oscillations
19.9.1 My Op Amp Rings at 1 MHz When I Put This Cable on It
19.9.2 When I Wave at It, It Waves Back
19.9.3 My Circuit Works Until I Let Go of It
19.9.4 My Transistor Amplifier Oscillates at 100 MHz
19.9.5 Another Kind of Digital Troubleshooting
19.10 Other Common Problems
19.11 Debugging and Troubleshooting Optical Subsystems
19.12 Localizing the Problem
19.12.1 Is It Optical or Electronic?
19.12.2 Component Tests
19.12.3 Beam Quality Tests
19.12.4 Collimated Beam Problems
19.12.5 Focused Beam Problems
19.12.6 Viewing Techniques
19.12.7 Test Techniques for Imaging Systems
19.12.8 Test Techniques for Light Buckets
19.12.9 Invisible Light
19.12.10 Test Techniques for Fiber Systems
19.12.11 Test Techniques for Frequency‐Selective Systems
19.12.12 Source Noise Problems
19.12.13 Pointing Instability Problems
19.12.14 Source Pulling
19.12.15 Misalignment
19.12.16 Etalon Fringes
19.12.17 Thermal Drift
19.12.18 Environmental Stuff
19.12.19 Take It Apart and Put It Together Again
Chapter 20 Thermal Control
20.1 Introduction
20.1.1 Temperature Control Regimes
20.2 Thermal Problems and Solutions
20.2.1 Thermal Expansion
20.2.2 Compliant Mounts
20.2.3 Athermalization
20.2.4 Thermal Gradients and Bending
20.2.5 Temperature and Young's Modulus
20.3 Heat Flow
20.3.1 Heat Conduction in Solids
20.3.2 “Thermal Mass”
20.3.3 3D Heat Conduction
20.3.4 Thermal Properties of Materials
20.3.5 Thermal Interfaces
20.3.6 Interfacial Thermal Resistance
20.3.7 Dry vs. Greased Interfaces
20.3.8 Greased Joint Problems
20.3.9 Thermal Gap Pads
20.3.10 Heat Conduction in Gases
20.3.11 Convection
20.3.12 Radiative Transfer
20.3.13 Getting Uniform Air Temperature
20.4 Insulation
20.4.1 Insulation and Thermal Radiation
20.4.2 Styrofoam
20.4.3 Dewars
20.4.4 Condensation
20.5 Temperature Sensors
20.5.1 IC Sensors
20.5.2 Thermistors
20.5.3 Platinum RTDs
20.5.4 Thermocouples
20.5.5 Diodes
20.5.6 Phase Change Sensors
20.5.7 Preventing Disasters: Thermal Cutouts
20.6 Temperature Actuators: Heaters and Coolers
20.6.1 Electric Heaters
20.6.2 PTC Thermistors
20.6.3 Thermoelectric Coolers
20.6.4 TECs, Thermal Loads, and Heat Leaks
20.6.5 Heat Sinking TECs
20.6.6 Mounting TECs
20.6.7 Stacking TECs
20.6.8 Connecting to TEC Stages
20.6.9 Modeling TECs
20.7 Heat Sinks
20.7.1 Natural Convection
20.7.2 Forced Air
20.7.3 Water Cooling
20.7.4 Phase Change Cells
20.7.5 Attaching Devices
20.7.6 The TEC Control Problem
20.7.7 Controlling TECs
20.7.8 Mechanical Refrigerators
20.7.9 Expendable Coolant Systems
20.8 Temperature Controller Design
20.8.1 High‐Precision Control
20.8.2 How Fast Can We Go?
20.8.3 Local Feedback Loops
20.8.4 Handling Gradients
20.8.5 Is the Sensor Temperature What You Care About?
20.8.6 Dissipation on the Cold Plate
20.9 Temperature Controllers
20.9.1 Bang–Bang Controllers: Thermostats
20.9.2 Linear Control
20.9.2.1 Proportional Loops
20.9.2.2 Integrating Loops
20.9.2.3 Derivative Terms
20.9.3 Frequency Compensation
20.9.4 Frequency Compensating Slow Loops: Integrator with Time Delay
20.9.5 Testing and Optimization of Temperature Controllers
20.9.6 Thermal Simulations: A Hack
Appendix A Good Books
A.1 Why Books?
A.2 Good Books for Instrument Builders
Mathematics
Mathematical Tables
Electromagnetics
Optics
Other Physics
Circuits
Noise and Interference
Optomechanics
Detection and Front Ends
Measurements and Systems
Construction
Lasers
Digital Signal Processing and Numerical Analysis
Handbooks Worth Having
Notation
Physical Constants and Rules of Thumb
Index
EULA