Here we demonstrate fixed frequency, synchronously pumped, broadly tuneable optical parametric oscillators in the fs- and ps- time regime on the basis of periodically poled crystals. Up to 500nm tuning can be achieved in the NIR with fixed pump frequency and a single optics set. The key feature is a novel optics set up for tuning synchronously pumped broadband resonators. The use of a ring resonator for intra cavity SHG generation leads to highly efficient generation of pulses in the VIS range. Automated tuning makes it an ideal tool for MPE- and SHG microscopy. (c) 2005 Optical Society of America.