Fluke 56X - Manual (Page 26)

56x
Users Manual
18
Distance and Spot Size
As the distance (D) from the object being measured increases, the spot size (S)
of the area measured by the unit becomes larger. The relationship between
distance and spot size (D:S) for each unit is shown in Figure 7. The spot sizes
indicate 90 % encircled energy.
56 8
D:S=12:1
3 8 mm @
300 mm
75 mm @
900 mm
132 mm @
1500 mm
1.5 " @
12 "
3 " @
36 "
5.3 " @
60 "
S
D
561
eyl06a.eps
Figure 7. Distance and Spot Size