Microactuators : Springer : 9780792380894 : 0792380894 : 31 Dec 1997 : 219 8. 2 Sensors 221 8. 3 Physical Sensors 222 8. 3. 1 Electrical Sensing Means 223 8. 3. 2 Magnetic Field Methods 231 8. 3. 3 Optical Methods 232 8. 4 Chemical Sensors 241 8. 4. 1 Electrical Gas and Chemical Sensors 243 8. 4. 2 Guided-Optics Intrinsic Chemical Sensors 246 8. 4. 3 Extrinsic Chemical Sensors 250 8. 4. 4 Polymer Waveguide Chemical Sensors 251 8. 4. 5 Surface Plasmon Chemical Sensors 252 8. 4. 6 Indicator-Mediated Extrinsic Sensing 253 8. 4. 7 Optical Biosensors 256 8. 4. 8 Ultrasonic Gas and Chemical Sensors 257 8. 4. 9 Intelligent Sensors 258 8. 5 Connections/Links and Wiring 258 8. 5. 1 Optical Links 260 8. 5. 2 Requirement on the Processing Unit/Intelligence 262 8. 6 Actuators 263 8. 7 Signal Processing/Computing 264 8. 7. 1 Implicit Computation 266 8. 7. 2 Explicit Computation 267 8. 8 References 274 Subject Index 279 Micro-Actuators (Electrical, Magnetic, Thermal, Optical, Mechanical, and Chemica