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Related Experiment Video

Updated: Jun 17, 2026

The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements

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Published on: December 5, 2025

Phase-modulation method for AWG phase-error measurement in the frequency domain.

Kazumasa Takada¹, Tomohiro Hirose

¹Department of Electronic Engineering, Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho,Kiryu 376-8515, Japan. takada@el.gunma-u.ac.jp

|December 18, 2009

Summary

This summary is machine-generated.

We developed a phase-modulation method to measure arrayed waveguide grating (AWG) phase errors. This technique achieves high accuracy, even without carrier frequencies, for precise optical device characterization.

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Area of Science:

Photonics and Optical Engineering
Integrated Optics
Waveguide Devices

Background:

Arrayed waveguide gratings (AWGs) are crucial components in optical communication systems.
Accurate measurement of phase errors in AWGs is essential for device performance.
Existing methods may have limitations in accuracy or require specific signal conditions.

Purpose of the Study:

To introduce a novel phase-modulation method for measuring AWG phase error.
To enhance the accuracy and applicability of AWG phase error measurements.
To address limitations of previous measurement techniques.

Main Methods:

Developed a phase-modulation technique for frequency-domain analysis.
Integrated the method with a previously reported digital sampling technique.
Performed measurements on arrayed waveguide gratings.

Main Results:

Achieved a measurement accuracy of +/-0.055 radians for phase error.
Successfully measured phase error in the center 90% of waveguides.
Demonstrated effectiveness even when no carrier frequencies are present in the interferometer's beat signal.

Conclusions:

The proposed phase-modulation method offers a highly accurate approach for AWG phase error measurement.
This technique is robust and applicable under conditions where carrier frequencies are absent.
The findings contribute to improved characterization and design of AWG devices.