Choi, Jaebin Taal, Adriaan J. Meng, William L. Pollmann, Eric H. Stanton, John W. Lee, Changhyuk Moazeni, Sajjad Moreaux, Laurent C. Roukes, Michael L. Shepard, Kenneth L. 2024-01-19T17:02:28Z 2024-01-19T17:02:28Z 2021-09-02 2020-08 1932-4545 https://pubs.kist.re.kr/handle/201004/118342 This paper presents a device for time-gated fluorescence imaging in the deep brain, consisting of two on-chip laser diodes and 512 single-photon avalanche diodes (SPADs). The edge-emitting laser diodes deliver fluorescence excitation above the SPAD array, parallel to the imager. In the time domain, laser diode illumination is pulsed and the SPAD is time-gated, allowing a fluorescence excitation rejection up to O.D. 3 at 1 ns of time-gate delay. Each SPAD pixel is masked with Talbot gratings to enable the mapping of 2D array photon counts into a 3D image. The 3D image achieves a resolution of 40, 35, and 73 mu m in the x, y, and z directions, respectively, in a noiseless environment, with a maximum frame rate of 50 kilo-frames-per-second. We present measurement results of the spatial and temporal profiles of the dual-pulsed laser diode illumination and of the photon detection characteristics of the SPAD array. Finally, we show the imager's ability to resolve a glass micropipette filled with red fluorescent microspheres. The system's 420 mu m-wide cross section allows it to be inserted at arbitrary depths of the brain while achieving a field of view four times larger than fiber endoscopes of equal diameter. English IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC AVALANCHE-DIODE ARRAY SENSORS FILTER BRAIN Fully Integrated Time-Gated 3D Fluorescence Imager for Deep Neural Imaging Article 10.1109/TBCAS.2020.3008513 1 IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS, v.14, no.4, pp.636 - 645 IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 14 4 636 645 scie scopus 000562099400002 2-s2.0-85089801752 Engineering, Biomedical Engineering, Electrical & Electronic Engineering Article; Proceedings Paper AVALANCHE-DIODE ARRAY SENSORS FILTER BRAIN Single photon avalanche diode time-gated fluorescence imaging neural imaging computational imaging