Microwave ovens use glass instead of ceramic for several reasons:
Microwave Transparency: Glass is transparent to microwaves, which allows the microwaves to pass through and heat the food inside the oven. On the other hand, most ceramics are not transparent to microwaves and would block the energy from reaching the food, making them unsuitable for the oven's cooking function.
Safety: Glass is a non-reactive and non-porous material, meaning it won't interact with the microwaves or the food being heated. In contrast, certain types of ceramics might contain metal elements or glazes that can react with microwaves, potentially causing damage to the oven or even releasing harmful substances into the food.
Heat Resistance: Glass is designed to withstand high temperatures and thermal shocks, making it suitable for the extreme heat generated inside a microwave oven. While some ceramics can also handle high temperatures, they may be more prone to cracking or breaking when subjected to sudden temperature changes.
Microwave-Safe Labeling: Glass is commonly labeled as microwave-safe, indicating that it has been tested and proven safe for use in microwave ovens. This labeling is crucial for consumer safety and confidence.
Aesthetics and Visibility: Using glass for the oven's door and turntable allows users to see the food as it cooks, which is beneficial for monitoring the cooking progress and avoiding overcooking.
In summary, glass is chosen for microwave oven construction due to its transparency to microwaves, safety, heat resistance, microwave-safe labeling, and aesthetic advantages. It ensures efficient cooking without compromising food safety or the oven's structural integrity.