Abstract:Requirement and difficulties of intra stack measurement are analyzed. The state of the art in intra stack temperature and humidity measurement is presented. Methodologies in temperature(field) measurement are micro thermocouple (array), resistive temperature detector (array), infrared image, fiber bragg gratings and phosphor thermometry; while chromatography, tunable laser absorption spectrum, micro electronic humidity sensor and fiber bragg gratings are applied in humidity measurement. Comparison of the measurement technologies shows that micro sensors have good spatial and signal resolution with low cost, while optic fiber bragg gratings benefits in chemical inertness, immunity to electromagnetic interference and multiplexing capability, which has the most brilliant future.