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Blue energy upconversion emission in Tm3+-doped SiO2-P2O5 channel waveguides off-resonance pumped by infrared radiation is reported. The waveguide samples were excited by a single continuous-wave laser source at 1.064 μm. Two distinct blue emission signals around 450 and 480 nm, in addition to red at 660 nm and near-infrared at 800-nm less intense emissions were observed. The upconversion excitation mechanism was assigned to stepwise multiphoton absorption processes followed by nonradiative multiphonon-assisted relaxation processes. Infrared-to-blue conversion efficiencies with respect to the absorbed pump power of ∼6.0×10-7 for this off-resonance pumping scheme was measured. The dependence of the infrared-to-blue upconversion mechanism upon the excitation power and thulium content is also examined.