Faro FaroArm Fusion, Руководство пользователя

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FaroArm ® Manual
January 2009
43
Chapter 1: Introduction to the FaroArm
®
pointing at the surface, until the process completes. You can also set
the values manually:
• Exposure - How long the “shutter” is open and the sensor is
exposed to light in the camera. Enter a number from 1 to 80; the
corresponding value in milliseconds appears next to it. Light colors
and reflective surfaces are better captured with low exposure levels.
Darker colors typically require higher exposure levels. The default
value is 16.
• Noise Threshold - The Laser Line Probe measures the intensity, or
return power, of all pixels and each pixel of the laser line projected
onto a surface using a scale from 0 to 255. All data having intensity
below the Noise Threshold value is considered noise or “chatter”
that is too faint to be usable and is simply ignored. Dark colors or
surfaces that tend to absorb light may benefit from a lower value.
Increasing this value will filter out more data. Setting this value to
255 considers all data to be noise. The default value is 15.
Advanced Settings
• Select the A
DVANCED
S
ETTINGS
check box to modify more material
settings:
• Width Threshold - When determining the Center of Gravity (COG)
for the laser line, groups of pixels are analyzed. This sets the
minimum number of pixels to define a COG group of pixels. The
default value is 5. This means that if the Laser Line Probe picks up
several clusters of light in one column, due to angle of incidence,
reflection, or any other external interference, only clusters with at
least 5 pixels will be considered COG candidates. Pixels must also
meet the Noise Threshold criteria, which is a value of 2.
• Peak Threshold - For a COG group to be valid, one of the pixels
must be above this value. The default value is 50. Increasing the
Peak Threshold is useful with reflective surfaces that may shine or
produce flares in the Laser Line Probe. If a Laser Line Probe
column captures more that one laser light source, only the groups or
clusters with at least one pixel at Peak Threshold will be
considered. Groups must also meet Noise Threshold and Width
Threshold criteria.
• Algorithm - Select an exposure setting:
• Automatic - Full : As you digitize, the Exposure setting
automatically adjusts to maintain the proper saturation level. This
08M46E00_FaroArmUSB.book Page 43 Tuesday, February 17, 2009 1:42 PM