Fast and reliable technique for spatial coherence measurement with a temporally modulated nonredundant slit array

Area of Science:

• Optics and Photonics
• Quantum Optics
• Metrology

Background:

• Spatial coherence of light is a fundamental property.
• Accurate measurement of spatial coherence is crucial for various optical applications.
• Existing methods can be complex or limited in scope.

Purpose of the Study:

• To develop a novel, efficient method for measuring spatial coherence.
• To validate the method theoretically and experimentally.
• To demonstrate its applicability under challenging conditions.

Main Methods:

• Utilized a temporally modulated nonredundant slit array on a digital micromirror device.
• Formulated a general theory for spatial coherence measurement, not limited to the far field.
• Conducted experimental validation with a six-slit array.

Main Results:

• A single measurement accurately determined spatial coherence for 15 slit separations.
• The method proved effective even in the presence of unavoidable background light.
• Demonstrated high reliability and speed of the proposed technique.

Conclusions:

• The proposed digital micromirror device-based method offers a fast and reliable approach to spatial coherence measurement.
• This technique overcomes limitations of previous methods, including far-field constraints.
• It provides accurate results in practical scenarios with background light.