Open AccessMode-locked laser autocollimator with an expanded measurement range
Author(s) -
Yuan Liu Chen,
Yuki Shimizu,
Yukitoshi Kudo,
So Ito,
Wei Gao
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.015554
Subject(s) - optics , laser , collimator , tilt (camera) , photodiode , materials science , diffraction , femtosecond , physics , mechanical engineering , engineering
A mode-locked laser is employed as the light source of a laser autocollimator, instead of the conventionally employed single-wavelength laser, for an expanded range of tilt angle measurement. A group of the spatially separated diffracted beams from a diffraction grating are focused by a collimator objective to form an array of light spots on the focal plane of the collimator objective where a light position-sensing photodiode is located for detecting the linear displacement of the light spot array corresponding to the tilt angle of the reflector. A prototype mode-locked femtosecond laser autocollimator is designed and constructed for achieving a measurement range of 11000 arc-seconds.