Imaging in Short-Wave Infrared with 1.82 μm Pixel Pitch Quantum Dot Image Sensor

A high pixel density image sensor for the Short Wave Infrared (SWIR) range is presented. A PbS quantum dot (QD) photodiode array is monolithically integrated on a silicon custom readout IC. Imaging in VIS and SWIR is demonstrated using focal plane arrays with pixel pitch down to record 1.82 μm. Through-silicon vision and lens-free imaging (LFI) microscopy are shown as applications that can benefit from high resolution/small pixel dimensions. In the LFI demonstration, the captured hologram is computationally reconstructed to acquire SWIR microscopic images, resulting in a wavelength equivalent resolution LFI microscopy system. To our knowledge, this is the smallest pitch SWIR pixel ever reported and the first LFI system using a QD image sensor.