Adopting mask during proton implantation, we obtain several areas with different proton implantation in a. single wafer Of GaAs/AlGaAs asymmetrically coupled double quantum M ells (ACDQW) grown by M BE, and investigated the characteristics using photoluminescence (PL) and photo-modulated reflectance (PR) spectroscopy. Without rapid thermal annealing, the maximum transition energy shift of 82 meV in a single wafer has been obtained in different areas. The diffusion length of Al is deduced according to spectrum, and compared with that calculated by diffusion coefficient function. It might be very useful for both edge-emitting laser or VCSELs in GaAs-based materials to provide index guiding and better optical design for devices. It is also a good method to set up a library for optimizing the ion implantation processes.