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.

We have managed to reduce the measuring time of previously common hydrogel-based sensors from a few minutes to a few seconds. For this, the arrangement of the hydrogel in the sensor was changed so that the volume of the hydrogel could be reduced. The biggest challenge, apart from generating a very thin pattern, was to firmly bond the hydrogel to a silicon surface. This was to ensure that the resulting forces of the bimorph effect can be absorbed.

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.