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Field of View
The meter’s field of view is 50:1, meaning that if the unit is 50 inches from the
target, the diameter of object under test must be at least 1 inch. Other distances
are shown in the diagram at right. Make sure that the target is larger than
the meter’s spot size. The smaller the target, the closer you should be to it.
When accuracy is critical, make sure the target is at least twice as large as the
spot size. As the distance (D) from the object increases, the spot size (S) of the
area measured by the meter becomes large. The relationship between distance
and spot size is shown above. The focal point is 36" (914 mm). The spot sizes
indicate 90% encircled energy.
Safety
• Use extreme caution when the laser beam is turned on.
• Do not let the laser beam enter your eye, another
person’s eye or the eye of an animal.
• Be careful not to let the laser beam on a reflective
surface strike your eye.
• Do not allow the laser light beam to impinge on any gas which can explode.
