Abstract: Channel waveguides were fabricated by carbon implantation in soda lime glass samples doped with Er3+ and Yb3+, exhibiting good confinement and both monomode and multimode behaviour at 633 nm. Excitation at near infrared (NIR) and ultraviolet (UV) spectral ranges were used in order to obtain anti-Stokes (upconversion) and Stokes (downshift) emission in the visible range, respectively. The characteristic green and red bands of Er3+ transitions were observed, showing the potential of Yb3+ and Er3+ co-doping for the generation of visible guided emission under NIR excitation.