If the relative refractive index of the convex lens material is greater than the relative refractive index of the environment, then the lens converts the parallel light beam into a converging one. Such convex lenses are called collecting lenses. In contrast to convex lenses, concave lenses under the same conditions convert a parallel beam of rays incident on them into a divergent one. Therefore, such concave lenses are called scattering.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.