Fabrication of polymer compound microlens by lens-on-lens microstructures

- Polymer compound microlenses were designed and fabricated for dual focal imaging.
- The surface profile could be controlled by changing annealing temperature.
- Convex PCML has two real images, concave PCML has one real image and one virtual image.

We proposed a novel method for fabricating polymer compound microlenses (PCMLs) using micro-inkjet technique and subsequent curing process. Two different types of PCMLs with sandwich microstructure (PDMS-Glycerol-PDMS), concave and convex PCMLs, have been designed and fabricated in experiments. Convex PCML has two real images and two foci. The concave PCML has one real and one virtual focal planes, which can generate one real image and one virtual image respectively. Moreover, the diameter of concave PCML can be controlled by adjusting the curing time and temperature. The proposed method is simple, efficient and suitable for realizing large-scale high numerical aperture PCMLs array, which has potential applications in diverse optical systems such as optical storage and three-dimensional imaging.