Application of DVD/CD pickup optics to microscopy and fringe projection

We discuss a low-cost microscope that is constructed using commercial DVD and CD pickups and demonstrate its fine focus capacity and high resolution. Also, we demonstrate a fringe projection interferometer that uses the three-beam positioning system of a CD reader. We show that with a simple rotation of the grating placed inside the pickup head, an electrically controlled fringe-shift system is obtained, which can be used for 3D profilometry. Despite the low cost of these systems, they have a performance comparable to more complex systems.