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A lateral wavefront shearing interferometer with variable shear
1IBM Research Laboratory, San Jose,California 95114, USA.
Applied Optics
|January 12, 2010
Summary
A novel lateral wavefront shearing interferometer utilizes diffraction gratings for precise image manipulation. This optical instrument enables variable lateral shear for advanced applications.
Area of Science:
- Optics and Photonics
- Interferometry
- Diffraction Optics
Background:
- Traditional interferometers often face limitations in achieving variable lateral shear.
- The need for precise wavefront analysis drives innovation in interferometer design.
Purpose of the Study:
- To present a new lateral wavefront shearing interferometer design.
- To demonstrate experimental verification of the proposed interferometer principle.
- To explore a simplified configuration and a novel sine wave generator application.
Main Methods:
- Employing two diffraction gratings as beam splitters in Fraunhofer planes.
- Utilizing successive image-forming systems to create intermediate images.
- Achieving variable lateral shear through opposite grating rotation.
Main Results:
- Successful experimental verification of the lateral wavefront shearing interferometer principle.
- Demonstration of a simplified folding configuration with a single grating and image system.
- Development of a sine wave generator using an extended, polychromatic source based on the interferometer principle.
Conclusions:
- The presented lateral wavefront shearing interferometer offers a versatile and effective method for optical measurements.
- The design is adaptable, allowing for simplification and integration into new applications like sine wave generation.
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