title: Fabrication of a concave grating with a large line spacing via a novel dual-beam interference lithography method.
abstract: We introduce a novel dual-beam interference lithography (IL) method that makes it possible to fabricate a concave grating with a large line spacing. A concave lens is placed between two point sources for spatial interference and a concave substrate to produce the grating pattern. The original positions of the two point sources are separated by the concave lens, which permits the IL method to fabricate a concave grating that bypasses the line spacing limitation of the conventional IL system. A concave grating with a line spacing of about 3.8 μm was fabricated and fitted inside a miniature spectrometer. The enlarged line spacing reduces the detector length by 66.5%, while keeping the resolution better than 1.5 nm over a wide spectral band (360 - 825 nm).
authors.forename: Xinghui
authors.initials: X
authors.lastname: Li
authors.forename: Kai
authors.initials: K
authors.lastname: Ni
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhou
authors.forename: Xiaohao
authors.initials: X
authors.lastname: Wang
authors.forename: Rui
authors.initials: R
authors.lastname: Tian
authors.forename: Jinchao
authors.initials: J
authors.lastname: Pang