Medical masks have become necessary of late because of the COVID-19 outbreak; however, they tend to attenuate the energy of speech signals and affect speech quality. Therefore, this study proposes an optical-based microphone approach to obtain speech signals from speakers' medical masks. Experimental results showed that the optical-based microphone approach achieved better performance (85.61%) than the two baseline approaches, namely, omnidirectional (24.17%) and directional microphones (31.65%), in the case of long-distance speech and background noise. The results suggest that the optical-based microphone method is a promising approach for acquiring speech from a medical mask.