Sentence examples for minimum speckle size from inspiring English sources
The minimum speckle size in the pattern is given by the ratio L: L'.
Kirkpatrick et al. have shown through simulations that this effectively undersamples the speckle pattern, and that the minimum speckle size to avoid undersampling is twice the pixel spacing - a straightforward application of the Nyquist criterion [ 12].
The calculation region, generally a square, needs to be a multiple of the minimum speckle size and has often been set at 5 x 5 or 7 x 7 pixels [ 14, 15].
These images have a minimum speckle size s of 20 pixels and contrast K ranging between the ideal value of 1, for exposure of 0 units, and 0.41 for the longest exposure of 255 units as K approaches the predicted K 0 of 0.4.
The initial image was generated with a minimum speckle size s = 20 pixels, and subsequent images with smaller effective speckle sizes were produced by low-pass filtering using box-car filters with the sizes 1 to 128 pixels, followed by down-sampling, to generate a set of images with effective speckle sizes between 20 and 0.16 pixels.
The static elements are distributed randomly, with a uniform distribution throughout the L' by L' matrix in order that they will have approximately the same maximum separation, and the static and dynamic components of the speckle pattern will have the same minimum speckle size s.
The average speckle size is 2.8 pixels.
Increase in the subset size for DIC does not significantly improves the accuracy, while the smallest subset size depends on the speckle pattern and speckle size.
The imaged object should be prepared with a random speckle pattern of appropriate speckle size so that each interrogation window contain a unique image.
Dainty showed that the average speckle size is inversely proportional to the illuminated area [33].
Destrycker (2012) states that to isolate the effect of the speckle pattern, there should be a way of applying the speckle pattern in a controlled way, e.g. controlling the speckle size, the speckle size distribution, the grey value distribution and the actual colour of the black and white paint.
