Handbook of Plastic Optics	5
	Contents	7
	List of Contributors	13
	1 Introduction	15
	2 Optomechanics of Plastic Optical Components	21
	2.1 Introduction	21
	2.2 Configuration of Plastic Optical Elements	22
	2.2.1 Single-Function Elements	23
	2.2.2 Elements with Integrated Fixation Features	24
	2.2.3 High Functional Integration	25
	2.3 Mounting Plastic Optical Elements	29
	2.4 Dimensional Stability	32
	2.4.1 Structural Stability	32
	2.4.1.1 Resonant Frequency	32
	2.4.1.2 Deflection at Constant Thickness	33
	2.4.1.3 Deflection at Constant Mass	33
	2.4.1.4 Mass at Constant Deflection	33
	2.4.2 Thermal Stability	35
	2.4.2.1 Coefficient of Linear Thermal Expansion	35
	2.4.2.2 Thermal Conductivity	35
	2.4.2.3 Specific Heat	36
	2.4.2.4 Thermal Diffusivity	36
	2.4.2.5 Distortion Coefficients	36
	2.4.3 Moisture Expansion	38
	2.5 Tolerancing	38
	2.5.1 Tolerance Budgeting and Allocation	38
	2.5.2 Typical Tolerances and Specifications for Plastic Optics	41
	2.6 Optomechanical Simulation of Plastic Optical Elements	43
	2.6.1 Integrated Optomechanical Analysis	43
	2.6.2 Thermoelastic Analysis	44
	2.6.3 Stress Birefringence Analysis	45
	2.6.4 Thermo-optic Analysis	45
	2.6.5 Moisture Absorption Analysis	46
	2.6.6 Mold Flow Analysis	46
	3 Tooling for Injection Molded Optics	49
	3.1 Introduction	49
	3.2 Principles	50
	3.2.1 Main Parts of an Injection Mold	50
	3.2.2 Gate and Runner Design for Optical Molded Parts	53
	3.2.3 Hot and Cold Runner Molds	53
	3.2.3.1 Cold Runner	54
	3.2.3.2 Hot Runner	54
	3.2.4 Ejector Design	54
	3.2.5 Heating and Cooling	55
	3.2.6 Mold Height, Opening Stroke, and Ventilation	56
	3.2.7 Number of Cavities	56
	3.2.8 Consideration of Shrinkage	57
	3.2.9 Materials for Injection Molds	57
	3.2.9.1 Coatings	58
	3.2.10 Design Steps of Injection Molds for Plastic Optics	58
	3.2.10.1 Diamond-Turned Prototypes	58
	3.2.10.2 Prototype Mold	58
	3.2.10.3 Production Mold	59
	3.2.10.4 Production Mold Optimization	59
	3.3 Molding Variations	59
	3.3.1 Two-Component Injection Molding	59
	3.3.2 Compression Molding	60
	3.3.3 Injection-Compression Molding (ICM)	61
	3.3.4 Variothermal Injection Molding	61
	3.3.5 Micro-Injection Molding	62
	3.3.6 Liquid Silicone Rubber (LSR) Injection Molding	62
	3.4 Optical Mold Inserts	63
	3.4.1 Steel Polishing	64
	3.4.1.1 Mirror Finish	64
	3.4.1.2 Computer-Controlled Polishing	64
	3.4.2 Galvanic Replication	64
	3.4.3 Diamond-Turning Technology	66
	3.4.4 Insert Quality and Molded Parts	66
	3.5 Ultra-precision Machine Tools for Mold-Making	69
	3.5.1 Characteristics of an UP Machine Tool	69
	3.5.2 Some Words about the Environment	70
	3.5.3 Basic Process Features	70
	3.5.4 Tooling for Precision	71
	3.5.5 Typical Machine Configurations	72
	3.5.5.1 Single Axis	72
	3.5.5.2 Two-Axis SPDT	72
	3.5.5.3 Three-Axis SPDT	73
	3.5.5.4 Off-Axis SPDT	74
	3.5.5.5 Multi-Axis Freeform Operation	75
	3.5.6 Material-Related Limitations	78
	3.5.6.1 Overcoming Material Limitations	78
	4 Metrology of Injection Molded Optics	81
	4.1 Introduction	81
	4.2 Dimensional Metrology	84
	4.3 Surface Metrology	86
	4.3.1 General Concepts	86
	4.3.2 NANOMEFOS	88
	4.3.3 Deflectometry	89
	4.3.4 Tactile Profiling	92
	4.4 Wavefront Metrology	95
	4.4.1 General Concept	95
	4.4.2 Interferometry	96
	4.4.3 Interferometer and Aspheres	101
	4.4.4 Interferometry and Strong Aspheres	103
	4.4.5 Double Pass–Single Pass Interferometers	106
	4.4.6 Automated Interferometry – Jenoptik Example	107
	4.4.7 Microscope Interferometers	107
	4.4.8 Shack–Hartmann Sensors	109
	4.4.9 Other Wavefront Sensors – Shearing Interferometer	114
	4.5 Birefringence	115
	4.6 Centration Measurement	119
	4.6.1 Optical Centration Measurement	120
	4.6.2 Image Processing	122
	4.6.3 Mechanical Centration Measurement	123
	4.6.4 Centration of Aspherical Surfaces	123
	4.6.5 Centration of Multielement Systems	124
	4.7 Custom Setups	125
	4.7.1 SALDO	126
	4.7.2 Double Mirror System	127
	4.7.3 High Throughput MTF Testing of CMOS Camera Modules	130
	4.8 Concluding Remarks	131
	5 Optical Plastics	137
	5.1 Introduction	137
	5.2 Quality Requirements for Optical Plastics	138
	5.2.1 Transparency	138
	5.2.1.1 Molecular Structure	138
	5.2.1.2 Molecular Conformation	139
	5.2.1.3 Impurities	139
	5.2.2 Refractive Index	140
	5.2.3 Birefringence	143
	5.2.4 Stability	144
	5.2.4.1 Heat Resistance	144
	5.2.4.2 Moisture Absorption	145
	5.2.4.3 Residual Stress	147
	5.3 Plastics	148
	5.3.1 Acrylate Polymers	148
	5.3.1.1 PMMA	148
	5.3.2 Polycarbonate	153
	5.3.2.1 Optical Polycarbonate	153
	5.3.2.2 Low-Birefringence Polycarbonate: ST-3000	154
	5.3.3 Cycloolefin Polymer	155
	5.3.3.1 ZEONEX®/ZEONOR®	155
	5.3.3.2 Cycloolefin Copolymer (COC): APEL™/TOPAS®	159
	5.3.3.3 Norborne Functional Polymer: ARTON®	163
	5.3.4 Other Resin Materials	164
	5.3.4.1 Optical Polyester (O-PET)	165
	5.3.4.2 Polysulfone (PSU)	166
	5.4 Summary	168
	6 Coating on Plastics	175
	6.1 Introduction	175
	6.2 Deposition Techniques	176
	6.2.1 Physical Vapor Deposition	177
	6.2.2 Plasma-Enhanced Chemical Vapor Deposition	180
	6.2.3 Wet-Chemical Coating or Sol–Gel Coating	181
	6.3 Plasma Effects on Polymers	183
	6.3.1 Effects Caused by UV-Radiation	183
	6.3.2 Ion Bombardment Effects	184
	6.3.3 Conclusions for Coating Adhesion	185
	6.4 Stresses and Crack Formation	185
	6.5 AR Properties	188
	6.5.1 Optical Interference Coatings	189
	6.5.2 AR Design for Plastics	191
	6.5.3 AR Surface Structures	193
	6.6 Additional Functional Coatings	195
	6.6.1 Mirrors	195
	6.6.2 Electrically Conductive and Antistatic Layers	197
	6.6.3 Hydrophobic Topcoats	197
	6.7 Coating Experiences with Different Thermoplastics	198
	6.7.1 Polymethylmethacrylate	199
	6.7.2 Polycarbonate	199
	6.8 Test and Qualification Methods	200
	6.8.1 Optical Properties	200
	6.8.2 Adhesion	200
	6.8.3 Environmental Durability	201
	6.8.4 Abrasion and Scratch Resistance	202
	6.9 Summary and Outlook	203
	7 Production of Optical Components Using Plastic Injection Molding Technology	211
	7.1 Introduction	211
	7.2 Plastic Injection Molding	212
	7.3 Classification of Optical Components	213
	7.4 Process Chain of the Injection Molding of Optical Parts	215
	7.4.1 Basic Rules: Cleanliness and Repeatability	215
	7.4.1 Material and Material Feed	216
	7.4.2 Mold	216
	7.4.3 Injection Molding Machine	218
	7.4.3.1 Design of the Machine	218
	7.4.3.2 Machine Technology	219
	7.4.3.3 Equipment Installed on the Machine	219
	7.4.4 Automation and Downstream Processes	220
	7.5 Injection Molding–Injection Compression Molding	221
	7.5.1 Fundamental Difference	221
	7.5.2 Differences in Mold Technologies	222
	7.5.2.1 Main Axis Coining	223
	7.5.2.2 Auxiliary Axis Coining	223
	7.5.2.3 Conclusion	224
	7.5.3 Using the Clamping Unit for Injection Coining	224
	7.5.3.1 Summary	225
	7.5.4 Process Variants of Injection Compression Molding	225
	7.5.5 Example of Coining Tasks	228
	7.5.5.1 Manufacture of Ophthalmic Lenses	228
	7.5.5.2 Optical Data Carriers	228
	7.5.5.3 Active breathing	229
	7.6 Conclusion	230
	8 Cost Modeling of Injection-Molded Plastic Optics	233
	8.1 Introduction	233
	8.2 Different Uses and Users of Cost Modeling	234
	8.3 Calculating Plastic Optics Manufacturing Costs	235
	8.4 Mold Costs and Production Volumes	238
	8.5 Calculating Molding Costs	242
	8.5.1 Cycle Time and Cooling Time	243
	8.5.2 Yield and Machine Uptime	245
	8.5.3 Machine and Labor Costs	245
	8.5.4 Indirect Costs	247
	8.5.5 Material Costs	247
	8.6 Calculating Coating Costs	248
	8.7 Additional Processes	249
	8.8 Case Study 1: Comparing Different Design Concepts	249
	8.9 Case Study 2: Evaluating Manufacturing Process Improvements	255
	8.10 Case Study 3: Optimizing an Optical Design at Module Level	258
	8.11 Discussion and Conclusions	261
	9 Applications of Injection-Molded Optics	265
	9.1 Introduction	265
	9.1.1 Lighting Industry	266
	9.1.2 Mobile Communications	267
	9.1.3 Security	267
	9.1.4 Healthcare	268
	9.1.5 Sensors and Other Applications	268
	9.1.6 Photovoltaic	269
	9.2 Architectural LED Accent Lighting	270
	9.3 Freeform Lens for Logo Forming Illumination	272
	9.4 Optics for Street Lighting Luminaires	274
	9.5 Injection-Molded Transparent Silicone for High-Temperature and UV-Stable Optics	276
	9.6 Compact Camera for Mobile Applications	278
	9.7 Macrolens for an Add-on Microscope Device	280
	9.8 Camera Flash for Mobile Phones	283
	9.9 Extreme Aspheric Objective for 360° Camera System	285
	9.10 Snap-Mounted Optics Assembly	288
	9.11 Solar Fresnel Lenses	290
	9.12 Refractive–Diffractive Eyepiece	293
	9.13 Pentaprism Assembly	295
	9.14 High-Efficiency Microoptics for Illumination Projection Systems	297
	9.15 Eye Spectacles	299
	Index	301