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Eyes of insects in the nature have been evolved in assorted structures according to the place of residence, hours of living, or the way of perception. The structure of the insect eye not only has different composition that dissolve the incoming light according to its direction of origin, i.e., an apposition and a superposition eyes, but also has a wide field-of-view (FOV), a high spatial resolution, and a sensitivity. Conventional artificial compound eye cameras have limited features that only focus on one of the characteristics of the insect eye, such as lens diameter and lens barrel length. We report an optically adjustable ultrathin arrayed camera, which adjusts the FOV, lens diameter and focal length independently. The ultrathin arrayed camera consists of UV-curable resin based microlens array on CMOS image sensor and each lens is surrounded by a liquid-filled blocking layer to reduce optical cross-talks between neighboring lenses. Fabrication of the arrayed lens includes photolithography process of Au/Cr metal pattern on frontside and Cr pattern on backside of borosilicate glass. Each of the lenses are replicated from microhole arrays fabricated by isotropic wet etching of the borosilicate glass with HF (49%) etchant. The arrayed camera has adjustable lens diameter and curvature by etching time control and SU-8 post thickness control during photolithography. Fingerprint image was successfully obtained by an image processing from individual optical channels. This ultrathin arrayed camera will suggest a new approach to the development of light-filled camera and compact ultrathin camera in the medical, industrial, or military fields.
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