Sequoia LISST-HOLO, Руководство пользователя

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LISST-
HOLO User’s Guide
25
In this example, another 1024

1024 ROI has been added.
Note that the ROIs do not have to be aligned with each other.
Click the OK button when the ROI size and location is satisfying.
Note that the processing time doubles every time you add a new ROI.
The advanced button opens up the settings menu for the advanced
parameters.
The values listed in the window to the left are the factory default
settings.
With the exception of Minimum Threshold, Scale Length, Clean Stack,
and possibly the Index of Refraction, none of these values should ever
be changed unless instructed by Sequoia support personnel to do so.
The
Offset is the distance in mm from the receive window to the CCD
array. The reconstruction software needs this distance in order to
properly reconstruct the holograms. For the LISST-HOLO this value is
28 mm. DO NOT CHANGE THIS VALUE.
The
Pixel Size is the size of each pixel in micro-meters (µm). For the
LISST-HOLO the pixel size is 4.4 µm. DO NOT CHANGE THIS VALUE.
The
wavelength is the wavelength of the laser in nm. For the LISST-
HOLO the wavelength is 658 nm. The reconstruction software needs
this value in order to properly reconstruct the holograms. DO NOT
CHANGE THIS VALUE.
The
Index of Refraction is for the medium in which the LISST-HOLO is
being used. An average value for water is 1.333. If the LISST-HOLO is
used in air, e.g. for measuring pollen or snowflakes, the refractive index
should be changed to that for air; 1.0003.
The
Minimum Threshold is used for creating a composite image of all
the particles in the hologram. Decreasing this value will cause more
pixels to be identified as being a particle; increasing it will cause less
pixels to be identified as a particle.
Clean Stack is used to remove pixels that are less than a certain
percentage of the maximum gray scale value. Enter the percentage you
would like to be remove here (usually between 0% and 5%). This can be
useful for removing background noise.
The
Scale Length is the length of the scale bar (in µm) being added to
the composite images created during processing.
The
Minimum Particle Area
is a measure used to exclude ‘particles’
that could appear simply due to noise in the image. The default
minimum area is 9, meaning that unless a particle has a minimum area
of at least 9 coherent pixels (Equivalent Spherical Diameter of ~15µm),
it is being excluded from further consideration when computing size
distribution etc.
Click OK when you are satisfied with your selections.