Sensor Placement Strategies for Better PI Heater Temperature Feedback
https://heater-technology-guide.vantagequill.com/posts/how-to-choose-an-ito-glass-heater-for-optical-applications
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