Polymer waveguides are successfully fabricated by a simple method, which is incorporated with a lithography-galvanic (LIGA)-like and micromolding process. The refractive index of the UV polymer used in these experiments is changed by an extremely low electric field. The measured propagation loss is 0.32 dB/cm for 1.3 µm and 0.30 dB/cm for 1.55 µm. This process is easy, simple, and suitable for mass production.
We have developed a soft lithography method to replicate polymer waveguides. In this method, the waveguides are produced by a two-step molding process where master mold is first formed on a negatively tone phototresist and subsequently transferred to a PDMS mold, and silicone rubber mold is then used as a stamp to transfer the final waveguide pattern onto a UV cure epoxy. Initial results show good pattern transferring in physical shape. The optical performance is measured based on the propagation loss. In our design, the measurement was measured at 0.26 dB/mm for 1.3μm and 0.24 dB/mm for 1.55μm.
This paper describes a simple and inexpensive technique to design and fabricate polygon microlens array using thermal pressing technique. Polygon microlens array molds were fabricated by using lithography and electroforming process. Microlens pattern was designed on a photomask and transferred to a substrate through photoresist patterning. The electroforming technology was used to convert the photoresist microlens patterns into metallic molds. A hot pressing machine was used to replicate microlens array in PC substrate. The compression pressure, temperature, and pressing time were key parameters to design and manufacture microlens array. The optical properties of these microlenses have been characterized by measuring their focal lengths. The average cylindrical microlenses radii of curvature were 315μm~420μm and the average sag heights were 2.98μm~4.03μm.