The good quality of 200 pairs of highly strained In0.24GaAs/GaAs multi-quantum-well (MQW) structure is demonstrated by the x-ray diffraction and photoluminescence curves. Large-area modulators based on the pseudomorphic In0.24GaAs/GaAs MQW are designed and fabricated successfully, where the diameters are not less than 3 mm and the working wavelength is extended to 1064 nm. The single pass modulation depth is demonstrated to be 0.34 at 1064 nm at a reverse voltage of 80 V.