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Published on: March 22, 2019
In-sensor multispectral perception for near- and mid-infrared discrimination
Shi Fang1, Fakun Wang1,2, Fengqi Cui3
1School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore, Singapore.
Abstract:
Multispectral features across visible (Vis), near-infrared (NIR) and mid-infrared (MIR) provide complementary information for intelligent vision in challenging environments. Precise extraction of multispectral features within the sensor level becomes increasingly critical, yet remains elusive for next-generation vision systems. Here we report a multispectral sensor constructed by a MoTe2/BP heterojunction with gate-tunable band alignments between type-Ⅰ and type-Ⅱ, enabling bipolar Vis/NIR (473 ~ 1064 nm) and unipolar MIR (3.7 and 4.6 μm) responses under zero bias for in-sensor Vis/NIR convolution and MIR target recognition. Beyond single-device operation, a 9×1 linear array validates device uniformity and preliminary array-level feasibility. Furthermore, the multispectral sensor extracts crosstalk-free Vis/NIR and MIR features under co-illumination of 980-nm and 3.7-μm light, increasing recognition accuracy from 28% to 84% in reconstructed system-level demonstrations. By fully leveraging the tunable 2D-material band structure, this work demonstrates a universal sensor configuration for multispectral perception with in-sensor processing functions.
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