The path-tracing simulation of light-field camera system: SurfCam/GrainCams for lunar surface exploration

The SurfCam is being developed to understand the microscopic lunar surface structures known as the fairy castle structure, composed of grains with an average size of a few tens of microns. It is designed as a microscopic light-field camera (LFC) and is one of the camera instrument packages in GrainCams, a candidate payload for NASA's Commercial Lunar Payload Services (NASA/CLPS). The light-field camera system allows for obtaining depth maps and 3D images of lunar surface structures on a scale of tens of microns by capturing a 4D light field. This camera system can be achieved by adding a microlens array (MLA) between the main optics and the sensor in a typical camera system. The Cycles render engine, a physically-based path-tracing (one of the ray-tracing types) renderer of Blender 3D software, helps to simulate realistic light-field images. We performed path-tracing simulations by configuring SurfCam's optics and creating test objects to confirm depth estimation results in Blender 3D. In this study, we present the results of simulated images and analyze them based on the current design of the SurfCam.