Mode conversion via wavefront shaping

In recent years, wavefront shaping has been utilized to control and correct distorted light for enhancing a bright spot, generation of a Bessel beam or darkening a complete area at the output of a scattering system. All these outcomes can be thought of as enhancing a particular mode of the output field. In this letter, we study the relation between the attainable enhancement factor, corresponding to the efficiency of mode conversion, and the field distribution of the target mode. Working in the limit of a thin diffuser enables not only a comparison between experimental and simulated results, but also allows for derivation of an analytic formula. These results shed light on the ability to use a scattering medium as a mode converter and on the relationship between the desired shape and the efficiency.