Artificial Compound Eyes Prepared by a Combination of Air-Assisted Deformation, Modified Laser Swelling, and Controlled Crystal Growth

Abstract

This study presents the manufacturing process of bioinspired compound (BIC) eyes. The hierarchical eyes were accomplished by a combination of (i) modified laser swelling, (ii) air-assisted deformation, and (iii) controlled crystal growth. The results show that the addition of nanostructures on the surface effectively improved the water repellent performance with a contact angle (CA) of ∼160° and generally decreased the reflection by ∼25% in the wavelength range of 400–800 nm than the planar surface. Apart from these properties, the BIC eyes showed good optical performance. The convex structure has a circular shape and aspherical profile; this provides optical uniformity and constant resolution (full width at half-maximum = 1.9 μm) in all the directions. Furthermore, the BIC eyes reduced the imaging distortion by 1.5/3.4 and 2.3/3.1 times along the x and y axes, respectively, under 10° and 20° incident lights than a single lens. In the light acceptance range, the image displays almost no distortion.

Fabrication of Waterproof Artificial Compound Eyes with Variable Field of View Based on the Bioinspiration from Natural Hierarchical Micro–Nanostructures

“…4f. According to the analyses of previous research [15,36], denser nanolenses increase the surface roughness of the PDMS film, which results in the enhanced hydrophobic performance of the surface. The WCAs of the surface of the PDMS films increase with increasing densities of nanolenses (determined by the distances D1-D4).…”

“…However, the high cost and time required for the complicated 3D fabrication process limit its fabrication efficiency for widespread applications. On the other hand, based on the planar MLAs manufactured via conventional methods, artificial compound eyes can be fabricated indirectly by deforming planar MLAs to curved MLAs using vacuum absorption and thermoplastic molding [15][16][17]. The deformation of MLAs film is a simple and efficient method for fabricating artificial compound eyes.…”

Mini-Review on Bioinspired Superwetting Microlens Array and Compound Eye

“…Reproduced from Li M. et al ( 2019a ) with the permission of the WILEY-VCH. Reproduced from Bian et al ( 2020 ) with the permission of Bian et al Reproduced from Raut et al ( 2015 ) and Li J. et al ( 2019 ) with the permission of the American Chemical Society. Reproduced from Li M. et al ( 2019b ) with the permission of Li et al…”

“…Superwetting structures can also be directly created on the top surface of the microlenses, allowing the whole MLA surface to be decorated with a layer of superwetting structures. Li J. et al ( 2019 ) reported a novel manufacturing strategy to prepare superhydrophobic MLA and ACE. A concave MLA was firstly achieved on the elastomer substrate by a template replication.…”

Investigation and Prediction on Regulation of Hydrophobicity of Polymethyl Methacrylate (PMMA) Surface by Femtosecond Laser Irradiation

“…The femtosecond laser has ultra-high peak power and ultra-short reaction time, which not only will realize high removal rate of polymer materials, but also ensure the smoothing of the prepared micro-nano structure. Furthermore, the femtosecond laser can be used to process flexible, repeatable, precise, and controllable microstructures on the surface of a variety of materials including polymers [19][20][21][22]. The Wenzel model [23] and Cassie-Baxter model [24] were proposed to predict the contact angle for all the micro/nano structures.…”