1. INTRODUCTION ................................................ 1
1.1. Solid state detectors ................................. 2
1.2. Imaging system applications ........................... 3
1.2.1. General imagery ............................... 6
1.2.2. Machine vision ................................ 7
1.2.3. Scientific applications ....................... 7
1.2.4. Military applications ......................... 8
1.3. Configurations ........................................ 8
1.4. Image quality ........................................ 11
1.5. Pixels, datels, disels, and resels ................... 13
1.6. References ........................................... 15
2. RADIOMETRY AND PHOTOMETRY .................................. 17
2.1. Radiative transfer ................................... 17
2.2. Planck's blackbody law ............................... 19
2.3. Photometry ........................................... 21
2.3.1. Units ........................................ 23
2.3.2. Typical illumination levels .................. 25
2.4. Sources .............................................. 26
2.4.1. Calibration sources .......................... 26
2.4.2. Real sources ................................. 27
2.5. Point sources and extended sources ................... 30
2.6. Camera formula ....................................... 31
2.7. Normalization ........................................ 35
2.8. Normalization issues ................................. 38
2.9. References ........................................... 42
3. CCD FUNDAMENTALS ........................................... 43
3.1. Photodetection ....................................... 44
3.1.1. Photogate .................................... 45
3.1.2. Photodiode ................................... 45
3.2. CCD array operation .................................. 45
3.3. CCD array architecture ............................... 54
3.3.1. Linear arrays ................................ 55
3.3.2. Full frame arrays ............................ 56
3.3.3. Frame transfer ............................... 57
3.3.4. Interline transfer ........................... 59
3.3.5. Progressive scan ............................. 64
3.3.6. Time delay and integration ................... 66
3.3.7. Super CCD .................................... 70
3.4. Charge conversion (output structure) ................. 71
3.5. Correlated double sampling ........................... 72
3.6. Antibloom drain ...................................... 74
3.7. Low light level devices .............................. 77
3.7.1. Intensified CCDs(ICCD) ....................... 77
3.7.2. Electron bombarded CCD (EBCCD) ............... 80
3.7.3. Electron multiplying CCD (EMCCD) ............. 80
3.8. Charge injection device (CID) ........................ 82
3.9. References ........................................... 84
4. CMOS FUNDAMENTALS .......................................... 86
4.1. CCD and CMOS arrays: key differences ................. 87
4.1.1. CCD array characteristics .................... 87
4.1.2. CMOS array characteristics ................... 89
4.2. CMOS arrays: predictions and reality ................. 90
4.2.1. Smaller pixel potential limitations .......... 91
4.2.2. Smaller pixel design evolution ............... 93
4.3. Pixel electronics .................................... 94
4.3.1. 3T CMOS pixel family ......................... 95
4.3.2. 3T rolling shutter ........................... 98
4.3.3. 4T, 5T, AND 6T CMOS pixels ................... 99
4.3.4. Snapshot or simultaneous and global shutter
readout mode ................................ 101
4.4. CMOS architectures .................................. 102
4.5. CMOS future ......................................... 104
4.6. References .......................................... 108
5. ARRAY PARAMETERS .......................................... 110
5.1. Well capacity ....................................... 110
5.2. Number of detectors ................................. 110
5.3. Dark pixels ......................................... 112
5.4. Video chip size - optical format .................... 114
5.5. Microlenses ......................................... 116
5.6. Color filter arrays ................................. 118
5.7. Defects ............................................. 121
5.8. References .......................................... 122
6. ARRAY PERFORMANCE ......................................... 123
6.1. Quantum efficiency .................................. 124
6.1.1. CCDs, CMOS, and EMCCDs ...................... 125
6.1.2. ICCD and EBCCD .............................. 135
6.2. Responsivity ........................................ 136
6.2.1. CCD, CMOS, and EMCCD ........................ 137
6.2.2. Super CCD ................................... 145
6.2.3. ICCD and EBCCD .............................. 145
6.3. Dark current ........................................ 147
6.4. Maximum signal ...................................... 150
6.5. Noise ............................................... 151
6.5.1. Shot noise .................................. 154
6.5.2. Reset noise ................................. 155
6.5.3. On-chip amplifier noise ..................... 155
6.5.4. Off-chip amplifier noise .................... 157
6.5.5. Quantization noise .......................... 157
6.5.6. Pattern noise ............................... 158
6.5.7. Super CCD noise ............................. 160
6.5.8. EMCCD noise ................................. 161
6.5.9. ICCD noise .................................. 163
6.6. Dynamic range ....................................... 164
6.7. Photon transfer and mean-variance ................... 166
6.8. Array signal-to-noise ratio ......................... 171
6.8.1. CCD, CMOS, and Super CCD SNR ................ 171
6.8.2. EMCCD SNR ................................... 173
6.8.3. ICCD SNR .................................... 174
6.9. Noise equivalent Inputs ............................. 176
6.10. Lux transfer ........................................ 178
6.11. Speed-ISO ........................................... 185
6.12. References .......................................... 186
7. CAMERA DESIGN ............................................. 189
7.1. Camera operation .................................... 190
7.2. Optical design ...................................... 191
7.3. Analog-to-digital converters ........................ 191
7.4. Image processing .................................... 193
7.4.1. The knee .................................... 193
7.4.2. Aperture correction ......................... 194
7.4.3. Color correction ............................ 194
7.4.4. Gamma correction ............................ 197
7.5. Video formats ....................................... 199
7.5.1. "Conventional" video timing ................. 201
7.5.2. Digital television .......................... 203
7.6. CRT overview ........................................ 204
7.6.1. Monochrome displays ......................... 205
7.6.2. Color displays .............................. 206
7.7. Flat panel displays ................................. 208
7.8. Computer interface .................................. 209
7.9. References .......................................... 209
8. LINEAR SYSTEM THEORY ...................................... 211
8.1. Linear system theory ................................ 212
8.1.1. Time varying signals ........................ 212
8.1.2. Spatially varying signals ................... 215
8.2. Electronic imaging system ........................... 216
8.3. MTF and PTF interpretation .......................... 217
8.4. Superposition applied to optical systems ............ 219
9. MTF ....................................................... 222
9.1. Frequency domains ................................... 223
9.2. Optics MTF .......................................... 226
9.3. Detectors ........................................... 229
9.3.1. Rectangular ................................. 230
9.3.2. Circular .................................... 232
9.3.3. L-shaped .................................... 233
9.3.4. Notched rectangle ........................... 233
9.4. Diffusion MTF ....................................... 235
9.4.1. Bulk diffusion .............................. 235
9.4.2. Surface lateral diffusion ................... 236
9.4.3. Epitaxial layer diffusion ................... 237
9.6. Charge transfer efficiency .......................... 240
9.7. TDI ................................................. 244
9.8. Motion .............................................. 247
9.8.1. Linear motion ............................... 247
9.8.2. Random motion (jitter) ...................... 249
9.9. Electronic filters .................................. 252
9.9.1. Anti-alias analog filter .................... 252
9.9.2. Digital filters ............................. 253
9.9.3. Sample-and-hold ............................. 257
9.9.4. Post-reconstruction filter .................. 258
9.9.5. Boost ....................................... 259
9.10. CRT display ......................................... 260
9.10.1. Addressability .............................. 263
9.10.2. Character recognition ....................... 267
9.10.3. Display MTF ................................. 270
9.11. Flat panel displays ................................. 271
9.12. Printer MTF ......................................... 272
9.13. The observer ........................................ 273
9.14. Intensified CCD ..................................... 275
9.15. References .......................................... 277
10. SAMPLING .................................................. 279
10.1. Sampling theorem .................................... 281
10.2. Aliasing ............................................ 284
10.3. Array Nyquist frequency ............................. 286
10.3.1. Monochrome ................................. 286
10.3.2. CFA ........................................ 288
10.3.3. Super CCD .................................. 288
10.4. Optical low pass filter (OLPF) ...................... 290
10.5. Reconstruction ...................................... 293
10.6. Image distortion .................................... 296
10.7. Sampling "MTF" ...................................... 298
10.8. Spurious response ................................... 299
10.9. Multiple samplers ................................... 302
10.10.References .......................................... 303
11. IMAGE QUALITY ............................................. 305
11.1. Resolution metrics .................................. 307
11.2. Optical resolution .................................. 309
11.3. Detector resolution ................................. 310
11.4. Electrical resolution metric ........................ 311
11.5. MTF-based resolution ................................ 312
11.5.1. Limiting resolution ......................... 312
11.5.2. Optics-detector subsystem ................... 313
11.5.3. Schade's equivalent resolution .............. 318
11.6. Display Resolution .................................. 320
11.6.1. Disels ...................................... 320
11.6.2. TV resolution ............................... 323
11.6.3. Flat panel displays ......................... 324
11.6.4. Printers .................................... 324
11.7. Observer-based resolution ........................... 325
11.7.1. MTFA ........................................ 325
11.7.2. Subjective quality factor ................... 326
11.7.3. Square-root integral ........................ 328
11.7.4. Targeting task performance .................. 329
11.8. Viewing distance .................................... 330
11.9. Image reconstruction ................................ 334
11.10.References .......................................... 336
12. RANGE PERFORMANCE ......................................... 338
12.1. Atmospheric transmittance ........................... 338
12.2. Target contrast ..................................... 340
12.3. Contrast transmittance .............................. 340
12.4. Range predictions ................................... 342
12.5. References .......................................... 345
APPENDIX ...................................................... 347
f-number .................................................. 347
INDEX ......................................................... 349
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