To make TOF measurements, an avalanche photodiode (APD) (C12702, Hamamatsu) and a fold mirror were added to the optical setup as illustrated in the schematic in Fig. 1 (a). A 3D printed mount to reduce cross-talk between transmitting and receiving optical passes was also added as illustrated in Fig. 1 (b).
As illustrated in Fig. 1 (a), the laser pulse travels from the collimating objective through an adjustable aperture and is directed by a fold mirror onto the DMD at a 30º incident angle.