An optical signal detection system includes a plurality of photodetectors configured to detect optical signals reflected from an environment surrounding the optical signal detection system and convert the optical signals into electrical signals. The optical signal detection system also includes an amplifier coupled to the plurality of photodetectors. The amplifier is shared by the plurality of photodetectors and configured to generate an output signal by amplifying an individual electrical signal converted by a corresponding photodetector. The optical signal detection system further includes a multiplexing circuit configured to selectively establish a connection between one of the plurality of photodetectors and the amplifier to amply the electrical signal converted by that photodetector.