Ms. Takei, a 2nd year master's student, presented a paper at CLEO2021.

CLEO2021 (Conference on Lasers and Electro-Optics), the world's largest international conference on lasers and electro-optics was held from May 9th to 14th of the year. Continuing from last year, this year's CLEO 2021 was held in a virtual format for the entire schedule.
At this conference, Ms. Takei, a second year master's student, submitted her research results as a paper and it was accepted as an oral presentation. Ms. Takei has already presented papers in last year's CLEO2020 and in CLEO Pacific Rim 2020. In the papers, she mentioned that the distribution of optical fiber birefringence in the fiber longitudinal direction can be measured with high resolution by applying coherent heterodyne detection technology and digital signal processing technology to the Rayleigh backscattered light measurement method of optical fiber.
In the paper presented by Ms. Takei at this year's CLEO2021, the above method was further developed. Even when vibration is applied to the optical fiber at a frequency of 250 Hz using a piezo-electric element, the above method detects birefringence fluctuation due to vibration.
We will continue to develop this method and study various optical fiber measurement applications.

Presented paper
N. Takei and S. Ryu, "Dynamic measurement of fiber-birefringence spatial distribution by coherent heterodyne detection of Rayleigh backscattered light," CLEO 2021, paper SM1E.7, May 2021.