What kind of lens can be added to the mobile phone camera to take clearer photos?

Polarizer. The excellent function of polarizer is that it can selectively let the light vibrating in a certain direction pass through by rotating the lens. It is often used in color and black-and-white photography to eliminate or weaken the strong reflection of non-metallic surfaces, thus eliminating or reducing light spots. Therefore, a mobile phone camera with a polarizing lens will take clearer photos. Mobile phone cameras mainly include built-in cameras and external cameras. The built-in camera refers to the camera installed inside the mobile phone, which is more convenient to use.