Test system and test method for y-branch lithium niobate waveguide phase modulator

Abstract

A test system and a test method for a Y-branch lithium niobate waveguide phase modulator. The light source is split by a 1×N single-mode fiber coupler to couple the light to the input end of the Y waveguide, and the two output ends are connected to an optical power meter or an extinction ratio tester. The output of the optical power meter or the extinction ratio tester is written into the computer through the data transmission system, and the P~V quadratic nonlinear relationship is fitted according to the test data, and the output voltage V of the optical power meter is converted into the calibrated optical power P, which is substituted into The formula calculates the insertion loss fluctuation and the splitting ratio of the Y waveguide. Add the periodic signal of the required specific frequency, amplitude and waveform to the modulation electrode of the Y waveguide, filter in the modulation signal band, and calculate the residual intensity modulation of the Y waveguide. The invention can continuously sample data, continuously monitor multiple Y waveguide devices, measure parameters such as optical power, insertion loss fluctuation, splitting ratio, polarization crosstalk, and residual intensity modulation, and ensure data accuracy during the sampling process.

Description

technical field [0001] The invention relates to a test system and a test method of a Y waveguide, which are used for testing the fluctuation of the insertion loss, splitting ratio, polarization crosstalk and residual intensity modulation of the Y waveguide. Parameters such as pigtail output power and polarization crosstalk can also be tested for other integrated optics. Background technique [0002] The Y-branch lithium niobate waveguide phase modulator is a Y-branch-shaped strip waveguide made by proton exchange annealing technology on an X-cut Y-pass lithium niobate wafer. Utilizing the electro-optic characteristics of the lithium niobate material itself, the phase of the guided light can be changed by changing the refractive index in the waveguide region by an external electric field, so as to achieve the purpose of modulating the phase. The residual intensity modulation of the Y waveguide is an additional effect of the phase modulation. When the external electric field...

AI Technical Summary

Problems solved by technology

Due to the spectral response characteristics of the built-in detector of the optical power meter, the response rate of the detector to different wavelengths of radiation light is different, resulting in the inconsistency between the output voltage V of the detector and the actual optical power, resulting in test errors

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