Related Experiment Video
Updated: Jun 22, 2026

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
Published on: January 28, 2019
Estimation of multiple phases in interferometry in the presence of nonlinear arbitrary phase steps
Abstract:
A phase shifting device (PZT) which is commonly applied in interferometry for phase measurement, unfortunately, has a nonlinear response to the applied voltage. In certain configurations such as, holographic moiré, where incorporation of two PZTs yields multiple phase information regarding the two orthogonal displacement components, the nonlinear response of the two PZTs yields highly erroneous result. In this context, we present for the first time a method for compensating multiple nonlinearities in the PZTs. Experimental results show the feasibility of the proposed method. The statistical performance of this method is also verified by comparing with the Cramér-Rao lower bound.
Related Concept Videos
Interference: Path Lengths
Two special sources may be considered when they are in phase. This can be easily achieved by feeding the two sources from the same source. An example would be synchronizing the two speakers by feeding them with the same source, such as the sound waves produced by a tuning fork. This setup ensures that the two sources have the same frequency and are...
The Phase Rule
Time and frequency -Domain Interpretation of Phase-lead Control
The design of phase-lead control involves the strategic placement of poles and zeros to balance steady-state error and system...
Interference and Diffraction
Phase Contrast and Differential Interference Contrast Microscopy
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
Time and frequency -Domain Interpretation of Phase-lag Control
Phase-lag controllers do not place a pole at zero, but instead influence the steady-state error by amplifying any finite,...

