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Method for measuring the spot size of a laser beam using a boundary-diffraction wave.
1Central Research Laboratory, Hitachi, Ltd., Kokubunji, Tokyo 185, Japan.
Optics Letters
|September 11, 2009
Summary
A novel technique accurately measures laser beam spot size by analyzing boundary-diffraction waves. This simple method offers a reliable alternative for laser characterization.
Area of Science:
- Optics and Photonics
- Laser Technology
- Metrology
Background:
- Accurate laser beam characterization is crucial for various applications.
- Traditional methods for measuring laser spot size can be complex or require specialized equipment.
Purpose of the Study:
- To introduce a new, simple, and effective method for measuring laser beam spot size.
- To validate the proposed method by comparing its results with a standard technique.
Main Methods:
- Scanning a laser beam's spot transversely across a straight boundary.
- Observing and analyzing the intensity profile of the resulting boundary-diffraction wave.
- Utilizing a silicon nitride (Si3N4) straight pattern for the boundary.
Main Results:
- Successfully measured the spot size of a Helium-Neon (He-Ne) laser beam (wavelength 633 nm).
- The new method yielded a spot size of 8.3 micrometers.
- This result closely aligns with the 8.9 micrometers obtained using the established knife-edge method.
Conclusions:
- The presented boundary-diffraction wave method is a simple and accurate technique for laser spot size measurement.
- This method provides a viable and potentially more accessible alternative to existing techniques like the knife-edge method.
