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Related Experiment Video

Updated: Jun 25, 2026

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator

Published on: January 28, 2019

Deterministic convergence in iterative phase shifting.

Esteban Luna¹, Luis Salas, Erika Sohn

¹Universidad Nacional Autónoma de México, Instituto de Astronomía, Observatorio Astronómico Nacional,Apartado Postal 877, Ensenada, B.C. 22800, México. eala@astrosen.unam.mx

|March 12, 2009

Summary

This summary is machine-generated.

This study introduces a new iterative phase shifting method that deterministically identifies convergence. This advancement improves accuracy in optical surface metrology and other phase shifting applications.

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Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator

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Published on: February 12, 2014

Area of Science:

Optical Metrology
Interferometry
Surface Characterization

Background:

Iterative phase shifting methods in interferometry often lack a reliable convergence indicator.
Accurate phase computation is crucial for precise optical surface measurements.

Purpose of the Study:

To develop a novel iterative phase shifting method with deterministic convergence identification.
To enhance the accuracy and reliability of phase computation in interferometric measurements.

Main Methods:

A new iterative phase shifting algorithm was developed.
The method was implemented and tested using a home-built Fizeau interferometer.
Measurements were performed on optical surfaces polished to lambda/100 using the Hydra tool.

Main Results:

The new method deterministically identifies convergence, overcoming limitations of previous implementations.
Measurements of optical surfaces achieved an intrinsic quality better than 0.5 nm.
The technique demonstrated high precision in characterizing polished optical surfaces.

Conclusions:

The presented iterative phase shifting method offers a robust solution for determining convergence.
This technique significantly improves the accuracy of optical surface metrology.
Potential applications extend to fringe projection and other phase shifting techniques.