Roof prisms are optical devices used in binoculars and other optical instruments to invert and revert images. They consist of two prisms arranged in a specific way, allowing light to pass through while maintaining a compact design. This configuration helps produce a right-side-up image, making it easier for users to view distant objects. These prisms are commonly found in roof prism binoculars, which are popular for their lightweight and streamlined shape. The most common types of roof prisms are the Dach prism and the Porro prism, each offering different advantages in terms of size and optical performance.