title: Optic axis determination based on polarization flipping effect induced by optical feedback.
abstract: For many materials, particularly biological tissues, optic axis orientation directly correlates with the materials performance, such as refractive index. In this Letter, a system measuring the optic axis azimuth was built using the laser feedback method that the polarization state of laser output is linearly polarized when optic axis azimuth is consistent with the initial direction of the laser polarization, otherwise elliptical polarization will be observed. The polarization state of the laser output is highly sensitive to the relative position of the optic axis and the initial direction of the laser polarization. This may be used to determine the optic axis azimuth of a material with a high precision.
authors.affiliation: Department of Opto-electronic Engineering, College of Opto-electronic Science and Engineering, National University of Defense Technology, Changsha, China.
authors.forename: Wenxue
authors.initials: W
authors.lastname: Chen
authors.forename: Shulian
authors.initials: S
authors.lastname: Zhang
authors.forename: Xingwu
authors.initials: X
authors.lastname: Long