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This work describes two methods for the dynamic characterization of a microbolometer infrared camera. The time constant, parameter commonly used for microbolometers dynamic performance identification, has been addressed in literature with studies mainly focused on theoretical computation and only seldom supported by testing activity. In this paper, alternative methods for the dynamic characterization of infrared sensors are presented and related uncertainty budgets are assessed. The infrared camera NEC TH7102WX has been tested with the proposed methods and results have been compared. The microbolometer behavior has proved to strongly deviate from the common first order model so that the time constant is no more a characterizing parameter. Depending on the definition of "equivalent time constants", the measured parameters changed by more than 50%, with values ranging between 30 and 50 ms. [ABSTRACT FROM AUTHOR]

[Display omitted] • The linearity of thin-film thermometers with Cr-Au and Ti-Au deposited layers has been verified between −20 °C and 100 °C. • A setup for cryogenic testing of the deposited resistors has been designed and validated. • The maximum regression error at LN2 temperature is 0.4 °C if a third-order polynomial is used to calibrate the deposited thin-film thermometer. This work deals with temperature characterization of Cr-Au and Ti-Au deposited resistors on quartz crystal microbalances designed for Space. The advantage of the proposed configuration is that direct heating of the electrode's area can be obtained as well as a measurement of the quartz crystal temperature. In this view, characterization of the deposited materials is of primary importance to provide accurate temperature measurement and retrieve reliable results for thermogravimetric analyses. The behavior of the deposited material has been verified down to cryogenic temperatures. The characterization in cryogenic condition evidenced that the linearity error is limited to 4 °C at the liquid nitrogen temperature but the regression standard deviation can be reduced to one order of magnitude if a third-order polynomial is used to fit the experimental data. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The aim of this work is a technical review about Quartz Crystal Microbalance (QCM) sensors used in space missions, i.e. Space Shuttle flights, i.e. NASA Space Transportation System (NASA STS) and satellite missions, that aimed at monitoring the contamination generated by outgassing processes of materials onboard satellites and sensitive payloads. The contamination processes are critical for scientific instrumentation (e.g. optics, telescopes, detectors) because scientific measurements and performances can be jeopardized or worsened by uncontrolled contamination. This issue has been addressed by the space agencies, e.g. NASA, ESA and JAXA that have implemented many different studies to monitor the material outgassing and degradation in space environment. During the past years, the QCM sensors have become the baseline solution for measuring material outgassing and characterizing the on-orbit contamination environment. This work summarizes the main QCM applications in Space and their findings, providing an overview of the sensors' performances in terms of stability, power, data rate, measurement accuracy and resolution. Different QCM technologies will be compared highlighting the advantages of their use for the next space missions and instrumentations that require an accurate monitoring of contamination environment. In particular, due to more severe contamination requirements for next payloads and instrumentations, QCM sensors would be useful to estimate the cleanliness degree by evaluating the induced contamination and degradation on sensitive instrumentations. [ABSTRACT FROM AUTHOR]