What is Pixel pitch?
Pixel pitch is the distance between two adjacent pixels in the sensor, pixel center to pixel center.
A smaller pixel pitch generally provides greater resolution. For a constant resolution, however, a decreased pixel pitch means decreased sensor size, which also means that smaller optics can be used.
The drawback of smaller pixel pitch is that each pixel is smaller and thus receives less energy. This in turn, reduces the effective detection range of the thermal camera. Ultimately, the performance of a sensor depends more on the pixel design than the pixel size.