A new approach for determination of a mean speckle size in simulated speckle pattern

• 1D correlation method of a long vector for speckle size determination is presented.
• The new method and known average 1D correlation method are compared.
• No requirement to enlarge the area of speckle pattern detection.
• The new method brings more accurate results than the average 1D correlation method.

In this paper one-dimensional correlation method for determination of a mean speckle size is used, while two various approaches are presented. It is shown, that accuracy of the measurement by the method depends on a number of speckles in an evaluated one-dimensional intensity profile of detected speckle pattern. It is also shown, that a significant optimization of the method by reduction of a number of intensity values representing detected speckle patterns can be performed. This study is carried out for several speckle patterns generated through a numerical simulation of the speckle fields after reflection of a Gaussian beam off a rough object’s surface. Results of the determination of the mean speckle size are compared with theoretical predictions.