Jaebin Choi, Adriaan J. Taal, Eric H. Pollmann, Changhyuk Lee, Kukjoo Kim, Laurent C. Moreaux, Michael L. Roukes, Kenneth L. Shepard. A 512-Pixel, 51-kHz-Frame-Rate, Dual-Shank, Lens-Less, Filter-Less Single-Photon Avalanche Diode CMOS Neural Imaging Probe. IEEE Journal of Solid-State Circuits, volume 54, pages 2957-2968, November, 2019 DOI:10.1109/JSSC.2019.2941529

We present an implantable single-photon shank-based imager, monolithically integrated onto a single CMOSIC. The imager comprises of 512 single-photon avalanchediodes distributed along two shanks, with a 6-bit depth in-pixelmemory and an on-chip digital-to-time converter. To scale downthe system to a minimally invasive form factor, we substituteoptical filtering and focusing elements with a time-gated,angle-sensitive detection system. The imager computationallyreconstructs the position of fluorescent sources within a 3-Dvolume of 3.4 mm×600μm×400μm.