15
4.2.4
Measurement of Prism Lens
Measuring prism degree of prism lens consists of 2 ranges: 0 ~ 5 degrees and
5 ~ 20 degrees of prism.
1.
In the range of 0 ~ 5 degrees of prism, the value is read directly on the
eyepiece dividing plate.
A.
Place prism lens on the measurement bearing seat and turn diopter measuring
hand-wheel to make drone focus distinct.
B.
Turn astigmatism turning hand-wheel so that the middle one of 3 long green
lines of cross-line drone passes through center of eyepiece dividing plate.
C.
Prism degree and value of basal angle of prism lens are read on the eyepiece
dividing plate (Fig. 17).
Fig. 17 (2
∆
basal angle 30°)
*2.
In the range of 5 ~ 20 degrees of prism, prism compensator should be used.
A.
Turn diopter measuring hand-wheel to obtain distinct focus of drone.
B.
Turn adjusting knob of prism compensator so that drone is adjusted to a
proper position of eyepiece visual field.
