11
BX51WI
Fig. 5
Fig. 6
Fig. 7
4-2 Focusing Block
1
Using the Pre-focusing Lever
(Fig. 5)
}The pre-focusing lever prevents collision between the specimen and
objective and simplifies the focusing operation. After bringing the
specimen into approximate focus with the coarse adjustment knob, turn
the pre-focusing lever @ in the direction of the arrow to lock it. Hereafter,
the lower limit of the coarse adjustment will be limited at the position
where the lever is locked. When bringing a specimen in focus, approximate
focus can be obtained by simply lowering the coarse adjustment to the
stopper position so all you have to do more is control the fine adjustment
knob.
}The up/down movement using the fine adjustment knob is not limited.
# When the pre-focusing lever is locked, the coarse adjustment stroke
is limited by the mechanism and it cannot reach the previous upper
limit. If you want to control the coarse adjustment knob to the previous
upper limit, unlock the pre-focusing lever.
2
Using the Fine Adjustment Fast-Feed Knob
(Fig. 6)
}Fine focusing is usually possible while the rubber cap @ is attached.
However, when it is desirable to allow the fine adjustment knob to vary
focusing by a large amount, though this is not be as large as with the
coarse adjustment knob, the rubber cap can be removed and the pro-
vided fine adjustment fast-feed knob attached in place.
}If you remove the knob by loosening the screw clamping the fine adjust-
ment knob ³ from the opposite side, the fine adjustment can be con-
trolled using the tip or thick of your finger.
3
Using the Frost Switching Lever
(Fig. 7)
}Low observation light can be brightened by turning the frost switching
lever @ which controls the built-in frost filter, in the direction of the arrow.
However, although the brightness is increased, irregularity in lighting may
also increase.
4
Adjusting the Coarse Adjustment Knob Rotation Tension
(Fig. 5)
# Do not adjust the coarse adjustment knob rotation tension adjust-
ment ring (² in Fig. 5) because the belt interlocking of the ring with
the coarse adjustment knob on the front has been adjusted at the
factory. If the tension is varied, the accuracy of the pre-focusing lever
will deteriorate.
@
²
@
²
@
³
