We report on a flexible multiphoton imaging system, suitable for simultaneous and efficient excitation of red (DsRed), yellow (YFP), green (GFP) and blue (DAPI) fluorophores. We used a simple, compact laser system, consisting of a 1 m high energy diode-pumped oscillator and a tunable wavelength extension using a photonics crystal fibre. The combination of a near IR excitation wavelength, high energy per pulse for efficient three photon excitation and spectral extension for GFP excitation allows for high flexibility.We present experimental results of simultaneous and efficient imaging fluorophores couples from the UV to the red (DAPI-RFP, GFP-RFP). 飛秒激光器（飛秒光纖激光器）