Method for measuring the spot size of a laser beam using a boundary-diffraction wave
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1Central Research Laboratory, Hitachi, Ltd., Kokubunji, Tokyo 185, Japan.
Optics Letters
|September 11, 2009
Abstract:
A new and simple method for measuring the spot size of a laser beam is presented. In this method, the spot of a laser beam is scanned transversely across a straight boundary, and the intensity profile of the boundary-diffraction wave is observed. This intensity profile makes it possible to measure the spot size. The spot size of a He-Ne laser beam (wavelength 633 nm) has been measured to be 8.3 microm by using a Si3N4 straight pattern; this value is compared with 8.9 microm obtained by the knife-edge method.
