精密プレス成形による導光板端面への回折格子の製作  [in Japanese] Fabrication of a Diffraction Grating on End Face of a Light Guide Plate Using Imprint Lithography  [in Japanese]

We developed a novel nano-imprinting machine to transfer pattern on a side-surface of a substrate, unlike a conventional nano-imprinting machine which transfers pattern on an upper-surface of a substrate. For a micro-spectroscope, a diffraction grating was fabricated on an end face of a light guide plate using the developed imprinting machine. The pressure distribution and pattern resolution were evaluated. On the whole end-face with 1mm×20mm area, uniform pressure distribution was obtained. A 400nm-periodic-structure was also fabricated well on the end face. A silicon mold for the diffraction grating with the 10μm period and 100nm height was fabricated using photo-lithography and dry-etching techniques. By pressing the silicon mold, the diffraction grating with the 10μm period and 100nm height was fabricated well on the end face of the light guide plate. The optical characteristics were measured. The measured diffraction angles agreed well with the calculated values. The maximum error of the diffraction angle was 0.22% between-3 and 6th diffraction orders.