Open AccessPrism lens for beam collimation in a silicon photonic crystal beam-steering device
Author(s) -
Jun Maeda,
Daichi Akiyama,
Hiroyuki Ito,
Hiroshi Abe,
Toshihiko Baba
Publication year - 2019
Publication title -
optics letters/optics index
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.524
H-Index - 272
eISSN - 1071-2763
pISSN - 0146-9592
DOI - 10.1364/ol.44.005780
Subject(s) - optics , prism , beam steering , lens (geology) , beam divergence , collimated light , photonic crystal , materials science , beam (structure) , diffraction , waveguide , laser beam quality , physics , laser , laser beams
The doubly periodic Si photonic crystal waveguide operates as a nonmechanical beam-steering device that can be applied in light detection and ranging. In this Letter, we develop and describe a prism lens that collimates a fan-shaped beam, emitted from the waveguide independent of the steering angle. Its fundamental profile is investigated using a theoretical analysis for thick lenses, and then, its detailed aspherical design is obtained. In ray tracing, this prism lens suppresses the beam divergence to less than the diffraction limit in most of the targeted beam-steering range. The prism lens is fabricated by acrylic cutting, and its expected characteristics are observed.