What process happen at the side slits?

At the side slits of a structure, such as a waveguide or an optical device, several processes can occur, including diffraction and interference. When waves pass through these slits, they can bend and spread out, creating patterns of constructive and destructive interference. This phenomenon is crucial in applications like lasers and sensors, where precise control of light is necessary. Additionally, the side slits can facilitate the coupling of light into or out of the device, enhancing its functionality.