Choppers: Optomechatronic Devices for the Controlled Modulation of Light

We present our main contributions and current work regarding one of the most used mechatronic devices for optical applications: the choppers. The issues of the macroscopic choppers with rotating wheels are presented, with a focus on the chopping frequency and on the profile of the transmitted flux (the modulation function) generated. The profiles we have investigated theoretically for the classical chopper wheels, with linear margins, and for top hat light beam distributions are discussed. The new configuration of the “eclipse choppers” (with windows with circular margins) we have introduced to produce approximate triangular series of impulses is presented, and the modulation functions produced are characterized. An insight in the experimental part of the study we are currently working on is provided, from the prototype wheels we have manufactured to the optical setup built for the testing of the different geometrical configuration of wheels, and to the first results.