Fabrication of two-dimensional (2D) dot array structure for the 2D photonic crystal (PC) purpose with femtosecond laser induced two-photon photopolymerisation has been reported in recent years. The lateral size of such a kind of structures can be accurately controlled; however, due to the constant height/width aspect ratio associated with circular beam illumination, the dot height and dot diameter cannot be manipulated independently, which presents a hurdle for high performance 2D PC fabrication. We report in this paper a novel way to manipulate the height of 2D PCs by co-axially inserting different sized opaque disks (obstructions) into the collimated light beam. The dependence of the dot dimension on the obstruction size was investigated in detail and it was found that the height/width aspect ratio could be increased approximately 2.28 times from 1.21 to 2.76.
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