A Practical OEM Checklist for Specifying a PI Heater

https://precision-thermal-lab.meridiannest.com/posts/ito-glass-heater-vs-conventional-heating-elements-key-differences

In sensors, a pi heater must deliver heat in a controlled way. It uses a thin resistive foil circuit laminated in polyimide film. One useful trait is fast response. Still, local hot spots can change the result