The CRONUS laser is a novel, ultrafast laser expanding the possibilities of 2-photon microscopy. It provides two tunable (680–960 nm and 960–1300 nm) and one fixed (1025 nm) independent but synchronized femtosecond laser pulses. Its gap-free, broad tuning curves cover the entire excitation spectrum relevant for 2-photon microscopy applications. The CRONUS laser thus allows a free choice of fluorophores that can be excited simultaneously and moreover the detection of non-linear optical processes, such as second and third harmonic generation (SHG and THG).