Sequoia LISST-Holo2, Руководство пользователя

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16 LISST-Holo2
User’s Guide
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-
HOLO2 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-HOLO2 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-HOLO2 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-
HOLO2 is being used. An average value for water is 1.333. If the
LISST-HOLO2 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 Diameter is a measure used to exclude
‘particles’ that could appear simply due to noise in the image.
The default minimum diameter is 15 microns, meaning that
unless a particle has a minimum area of at least 9 coherent
pixels (Equivalent Spherical Diameter of ~15µm), it is being