The temperature dependence of the resonance frequency of quartz resonators can be used for thermal infrared sensors. The quartz chips must be very thin to obtain a good sensor signal. This work describes how to manufacture and package sensors with 5 µm thin chips. Different sensor layouts are ion beam etched; they influence the vibration of the resonators, which is shown by impedance measurements. The temperature coefficient of the resonance frequency is determined to be around 90 ppm K^-1.

In thermometry, the displayed temperature value of an object depends on the size of the object. This behaviour, the size-of-source effect, might be a major cause of measurement uncertainty in a thermoscene. The influence of diffraction and digitization can be described advantageously with the modulation transfer function. Especially with very small objects the displayed temperatures are too low. When imaging large objects, not only the edge areas are affected, but also the entire image.