Microwaves are focused inside a microwave oven through the use of a component called a waveguide and a stirrer or turntable system. Let's explore how these components work together to focus the microwaves:
Waveguide: The waveguide is a metal tube or channel that directs and guides the microwaves from the magnetron (the microwave's energy source) to the cooking chamber. It acts as a conduit for the microwaves, ensuring that they are delivered to the food in an organized manner.
Stirrer or Turntable: Inside the cooking chamber, a stirrer or a turntable system helps distribute the microwaves evenly. These mechanisms rotate or move the food during cooking, ensuring that all parts of the food are exposed to the microwaves, thereby promoting more uniform heating.
Stirrer: In microwave ovens equipped with a stirrer, a metal fan-like blade or baffle is placed in the waveguide. The stirrer rotates slowly, redirecting the microwaves in different directions. This movement helps to spread the energy more evenly throughout the cooking chamber.
Turntable: Many microwaves feature a turntable—a rotating glass plate or tray inside the cooking chamber. The turntable spins the food as it cooks, ensuring that different areas of the food receive equal exposure to the microwaves. This rotation helps minimize hot spots and cold spots, resulting in more consistent heating.
By combining the waveguide and either a stirrer or a turntable system, microwave ovens can focus the microwaves in a way that promotes even distribution of energy within the cooking chamber. This ensures that the food is heated more uniformly and reduces the likelihood of certain areas being undercooked or overcooked.
It's important to note that the focusing of microwaves primarily pertains to how they are distributed within the cooking chamber to achieve even heating. It does not involve focusing the microwaves to a specific point or concentrating them like a focused beam of light.