In recent years, there has been an increasing demand for underwater cameras that monitor the condition of offshore structures and check the number of individuals in aqua culture environments with long-period observation. One of the significant issues with this observation is that biofouling sticks to the aperture and lens densely and prevents cameras from capturing clear images. This study examines an underwater camera that applies material technologies with high inherent resistance to biofouling and computer vision technologies based on image reconstruction by deep learning to lens-less cameras. For this purpose, our prototype camera uses a coded aperture with 1k rectangular shape pinholes in a thin metal plate, such as copper, which hinder the growth of biofouling and keep the surface clean. Although images taken by lens-less cameras are usually not well formed due to lack of the traditional glass-based lens, a deep learning approach using ViT (Vision Transformer) has recently demonstrated reconstructing original photo images well and our study shows that using gated MLP (Multilayer Perceptron) also yields good results. On the other hand, a certain degree of thickness for bio-repellence materials is required to exhibit their effect the thickness of aperture is necessary to use apertures sufficiently thinner than the size of the pinholes to avoid unintentional reflection and absorption on the sidewalls. Therefore, we prepared a sufficiently thin plate for image reconstruction and now currently we conduct tests of the lens-less camera of the bio-repellence aperture with actual seawater environments to determine whether it can sufficiently demonstrate the biofouling effect compared with usual camera with only waterproof.

翻译：近年来，对用于长期观测的海上结构状态监测及水产养殖环境中个体数量核查的水下相机需求日益增长。此类观测面临的一个关键问题是生物附着物密集粘附于光圈和镜头表面，导致相机无法获取清晰图像。本研究探讨了一种水下相机系统，该系统将具有高固有抗生物附着性能的材料技术与基于深度学习的图像重建计算机视觉技术相结合，应用于无透镜相机。为此，我们设计的原型相机采用编码光圈，即在铜等薄金属板上制备包含1k个矩形针孔的阵列，这种结构能有效抑制生物附着生长并保持表面清洁。尽管无透镜相机因缺乏传统玻璃镜头通常无法直接形成清晰图像，但近期基于ViT（Vision Transformer）的深度学习方法已证明能有效重建原始图像，本研究进一步表明使用门控MLP（多层感知器）同样能取得良好效果。另一方面，为实现生物排斥效应，材料需要具备一定厚度；同时，为避免针孔侧壁产生非预期的反射与吸收，光圈厚度需远小于针孔尺寸。因此，我们制备了适用于图像重建的超薄金属板，目前正在实际海水环境中对该抗生物附着光圈的无透镜相机进行测试，以评估其相较于仅具备防水功能的常规相机是否能充分展现抗生物附着效能。