Optical Design of Microscopes George H. Seward Tutorial Texts in Optical Engineering Volume TT88 SPIE PRESS Bellingham, Washington USA
Preface xiii Chapter 1 Optical Design Concepts /1 1.1 A Value Proposition 1 1.2 Specimen Model 1 1.3 Detector Parameters 1 1.4 Numerical Aperture 1 1.5 Wave Propagation 2 1.6 Geometric Aberrations 3 1.7 Image Contrast 4 1.8 Manufacturing 5 1.9 Assembly 5 Chapter 2 Basic Microscope Concepts / 7 2.1 Magnification 7 2.2 Accommodation 7 2.3 Finite Tube Length 8 2.4 Infinity-Corrected Objective 9 2.5 Tube Lens 10 2.6 Ocular Lens 11 2.7 Refractive Objects 12 2.8 Diffractive Objects 14 2.9 Dark Field 14 Chapter 3 Basic Geometric Optics /17 3.1 Ray Tracing 17 3.2 Cardinal points 17 3.3 Stops 18 3.4 Gaussian Lens Formula 19 3.5 Image Types 21 3.6 Optical Power 21 3.7 Paraxial Optics 22 3.8 Relay Lens 23 3.9 Magnifier 24 vii
viii Chapter 4 Aberrations / 27 4.1 Seidel Aberrations 27 4.2 Chromatic Aberrations 29 4.3 Other Aberrations 29 4.4 Aspheric Surfaces 33 Chapter 5 Basic Physical Optics / 35 5.1 Importance of Physical Optics 35 5.2 Wave Equation 35 5.3 Refractive Index 36 5.4 Dispersion 40 5.5 Refraction and Reflection 41 5.6 Emission 43 5.7 Absorption 43 5.8 Evanescent Field 44 5.9 Space-Angle Product 45 5.10 Coherence 46 5.11 Airy Pattern 46 5.12 Gaussian Beam Propagation 48 5.13 Transfer Functions 49 5.14 Gaussian Estimate of Airy Pattern 50 5.15 Scatter 51 5.16 Interference Filters 51 Chapter 6 Fluorescence / 53 6.1 Absorption Parameters 53 6.2 Electron States 54 6.3 Energy Diagrams 55 6.4 Fluorophores 57 Chapter 7 Optical Design Metrics / 63 7.1 CAD Tools 63 7.2 Wavefront Error 63 7.3 Ray-Intercept Plot 64 7.4 Spot Diagram 66 7.5 Point-Spread Plot 66 7.6 Encircled-Energy Plot 68 7.7 Modulation Transfer Function 68 7.8 Edge Spread 69 7.9 Lens Report 69 7.10 Relative Illumination 70 7.11 Surface-Form Error 70 7.12 Manufacturing Standards 72
ix Chapter 8 Image Contrast / 73 8.1 Radiometry 73 8.2 Expression of Contrast 73 8.3 Shot Noise 75 8.4 Emittance Patterns 76 8.5 Angular Collection Efficiency 77 8.6 Spatial Collection Efficiency 78 8.7 Full-Pixel Contrast 79 8.8 Subpixel Contrast 80 8.9 Point-Source Contrast 81 8.10 Full-Pixel Airy Contrast 82 Chapter 9 Microlens Formats / 85 9.1 10XR Double Gauss 85 9.2 10XR Microlens 86 9.3 2XR Microlens 87 9.4 1X Microlens 88 9.5 2XR Telecentric Spectroscopy Lens 89 Chapter 10 Illumination Systems / 93 10.1 Condenser 93 10.2 Abbe Illumination 93 10.3 Nelson Illumination 94 10.4 Diffusers 95 10.5 Köhler Illumination 96 10.6 Matched Stops 98 10.7 Light-Emitting Diodes 98 10.8 Aspheric Plus Singlet Relay 100 10.9 Achromatic Aspheric Plus Doublet Relay 101 10.10 Abbe Condenser 101 10.11 Abbe Aspheric 101 10.12 Total Internal Reflection Fluorescence Illumination 103 Chapter 11 Cover Strata /105 11.1 Importance of Specimen Tolerance 105 11.2 Perfect 10X for Air 105 11.3 10X Objective with Cover Glass in Place of Air 106 11.4 10X Objective with Microscope Slide in Place of Air 107 11.5 40X Objective with Silica Cover in Place of Glass 108 11.6 40X Objective with Tilted Cover Glass 110 11.7 60X Objective with Silica Cover in Place of Glass 111 11.8 Strehl Ratio versus Optical Path Length 111
x Chapter 12 Objective Lenses /113 12.1 Formats 113 12.2 Aplanatic Surface 113 12.3 10X Plan Achromat 114 12.4 40X Fluor 115 12.5 60X Immersion TIRF 117 12.6 100XAplanat 121 12.7 1 OX Schwarzschild 122 12.8 20X Internal Parabola 123 Chapter 13 Tube Elements /127 13.1 Doublet Tube Lens 127 13.2 Doublet-Pair Tube Lens 127 13.3 Filter Types 129 13.4 Filter within a Finite Conjugate Distance 133 13.5 Warped Filter within an Infinity Correction 133 Chapter 14 Ocular Lenses /139 14.1 Eyepiece 139 14.2 Pupils 139 14.3 Kellner Ocular 140 14.4 Plössl Ocular 141 14.5 Erfle Ocular 142 Chapter 15 Sensors /147 15.1 CCD Sensors 147 15.2 Active Pixel Sensors 151 15.3 Photomultiplier Tubes 152 15.4 Film 154 Chapter 16 Human Vision /157 16.1 Physiology 157 16.2 Contrast Sensitivity Function 158 16.3 Point Spread of a Lens 159 16.4 Lateral Inhibition of the Retina 160 16.5 Temporal Feedback of Photoreceptors 162 16.6 Saccation Point Spread 163 16.7 Vision Research 165 16.8 Temporal Contrast Sensitivity Function 165
xi Chapter 17 Optical Materials /169 17.1 Glass Types 169 17.2 Glass Map 172 17.3 Fluorite 173 17.4 Short Flint 176 17.5 Anomalous Dispersion 176 17.6 Sellmeier Formula 177 17.7 Environmentally Safe Glass 179 17.8 Glass Code 180 17.9 Spectral Lines 180 17.10 Cost of Optics 180 17.11 Structural Materials 181 Chapter 18 Composition and Spectra of Materials /183 18.1 Glass Structure 183 18.2 Crown 183 18.3 Flint 184 18.4 Long Crown 186 18.5 Short Flint 186 18.6 Short-Flint Special 187 18.7 Environmentally Safe Short Flint 189 18.8 Dense Flint 191 Chapter 19 Advanced Concepts /195 19.1 Wave Equation 195 19.2 Refractive Index 196 19.3 Relative Partial Dispersion 198 19.4 Emission 199 19.5 Coherence 199 19.6 Gaussian Beam Power 201 19.7 Transfer Functions 202 19.8 Scatter 204 19.9 Interference Filters 205 19.10 Shot Noise 206 Appendix: Prescriptions / 209 Works Consulted / 229 Recommended Reading / 231 References / 233 Index / 237