Low-Mass Planar Photonic Imaging Sensor

The Low-Mass Planar Photonic Imaging Sensor is based on the Segmented Planar Imaging Detector for EO Reconnaissance (SPIDER) concept developed in collaboration with Lockheed Martin Advanced Technology Center. SPIDER replaces the traditional optical telescope and digital focal plane detector array with a densely packed interferometer array based on emerging photonic integrated circuit (PIC) technologies that samples the object being imaged in the Fourier domain (i.e., spatial frequency domain), and then reconstructs an image. This approach replaces the large optics and structures required by a conventional telescope with PICs that are accommodated by standard lithographic fabrication techniques (e.g., CMOS fabrication). The standard EO payload integration and test process which involves precision alignment and test of optical components to form a diffraction limited telescope is, therefore, replaced by in-process integration and test as part of the PIC fabrication that substantially reduces associated schedule and cost. Our final report covers the details of the Low-Mass Planar Photonic Imaging Sensor Concept and supports the discussions by presenting a prototype PIC that was developed under a DARPA funded effort. Then a SPIDER design tailored to a Europa mission is presented to show the improvements over a conventional Topographical Imager (TI), in which SPIDER collects 10× the area on the surface of Europa with 17× the resolution. The choices for PIC material platforms are investigated and specific designs for waveguides and integrated optical components are presented. SPIDER image modeling and reconstruction algorithms are explained and image simulations shown. Then initial experimental data from a prototype PIC are presented and discussed before a SPIDER technology roadmap is introduced.