Integrating a PI Heater Into Compact OEM Assemblies

https://modern-heating-elements.fairmontdigest.com/posts/mica-heater-design-considerations-for-efficient-heat-transfer

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