Broadband Microlens Arrays for Efficient Coupling into Photonic Imaging Devices

Physical Sciences Inc. (PSI) will develop a Coupling-Optimized Metalens for Broadband Imaging (COMBI) for efficient optical coupling into photonic integrated circuits. Phased array imaging devices consist of networked vertical grating couplers to perform single-pixel wide field-of-view imaging in a low size, weight, and power (SWaP) package. However, the performance of these devices is limited by coupling losses in and out of the chip. PSIÆs COMBI will address this performance shortfall by providing numerical aperture-matched diffraction-limited broadband focusing of light into the grating couplers on the phased array circuit while adding negligible weight. By employing industry-standard nanofabrication techniques, the COMBI will minimize lens performance variations compared to standard refractive microlens arrays. During Phase I, PSI demonstrated diffraction-limited imaging using a prototype COMBI onto a focal plane array at wavelengths of interest in the near infrared. Our Phase II program will mature the technology, scale the fabrication process, and enable integration with a photonic integrated circuit.