Microlens Arrays Fabricated from Self-Assembled Organic Polymers

5 Microlens Arrays Fabricated from Self-Assembled Organic Polymers 

Hayashi et al. apphed a self assembly of polystyrene beads to form two-dimensional (2D) lattices on glass substrates, and demonstrated their use as arrays of microlenses in imaging [11]. However, this method could provide only one array with one specific pattern. In addition, high quality images are hard to obtain from microlenses shaped like whole spheres [12]. 

Biebuyck et al. used selective dewetting of liquid prepolymers on a surface printed with self-assembled monolayers to fabricate arrayed microlenses made of an organic polymer [13]. Due to the low viscosity of the prepolymer required by this process, the microlenses fabricated using this method exhibited relatively small curvatures and thus short focal lengths [12]. 

Lu et al. described a self-assembly approach to fabricating patterned 2D arrays of microlenses with well-controlled lateral dimensions in the range of 

The maximum number of polymer beads that could be held in each hole was governed mainly by geometry—specifically the ratios between the diameter D and height H of the holes and the diameter d of the polymer beads. This a very high-yield process the self assembly success rates were as high as 95%. Because polystyrene is optically transparent down to the UV regime, these self-assembled polystyrene beads could directly function as patterned 2D arrays of spherical microlenses. 

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