WORKSHOP PAPER
Planar microlenses applied to SPAD pixels
Abstract
Wafer level planar microlenses are designed to improve the sensitivity of SPAD arrays, based on rigorous optical simulations. State of the art refractive microlens solution and designed planar microlenses: FZP microlenses and metamicrolenses, are implemented on STMicroelectronics 40nm CMOS testchips (32 ×32 SPAD array). Optical gain compared to the reference microlens of 1.3 and 1.9 are shown for FZP and metamicrolenses, respectively in characterization and simulation.Keywords
SPAD pixels, Planar microlenses, Optical simulations,References
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