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The Europa Imaging System (EIS) combines a Narrow-Angle Camera (NAC) and a Wide-Angle Camera (WAC) to explore Jupiter’s Icy moon Europa. EIS is designed to address high-priority geology, composition, ice shell and ocean science objectives with the challenges of imaging in a wide range of scenarios spanning fast, low-altitude flybys with rapidly changing geometry and illumination to high-altitude imaging of faint scenes. Images for both EIS cameras are taken with a 10-μm pixel-pitch, 4096×2048 frontside illuminated CMOS image sensor. To perform color pushbroom imaging, the NAC and WAC both have six 32-row broadband stripe filters. The WAC is an F/5.75, 46-mm focal length, 8- lens refractive telescope with a 48° × 24° FOV and an IFOV of 218-μrad, achieving 11-m pixel scale from a 50-km altitude over a 44-km-wide swath. The along-track FOV provides 3-line (forward, nadir, and aft) pushbroom stereo swaths enabling digital topographic models with 32-m spatial scale and 4-m vertical precision. In order to perform over a 400- 1050 nm bandwidth in the extreme radiation environment surrounding Europa, the design contains 4 different materials: fused silica, CaF2, and two radiation resistant glasses. Each lens, except the exposed front surface of Lens 1 (L1), is coated with a proprietary antireflective (AR) coating, which has been tested for durability and performance in varying temperature and radiation environments. The 25-mm thick fused silica L1 plays dual roles in the WAC telescope design to also protect the CMOS sensor from the intense radiation of the Jovian environment. The optomechanical design maintained the optical alignment through thermal and vibration environmental testing. The WAC was delivered to NASA’s Jet Propulsion Laboratory (JPL) and integrated to the Europa Clipper spacecraft in summer 2022.
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