How to design an actually good toaster with lessons from the 1940's

3-Second Blueprint (English)

1. Conventional timer-based toasters fail on frozen or dense bread unless manually adjusted, risking burnt slices afterward.
2. The 1940s Sunbeam Radiant Control toaster uses a bimetallic strip to sense bread temperature instead of relying on a timer.
3. Modern toasters could achieve even higher precision by reading bread surface temperature through a window with an IR sensor.