Focus Stop Lever; Centering The Condenser; Effects Of The Field Diaphragm - Optika Italy B-1000 Serie Manual De Instrucciones

9.10

Focus stop lever

The upper limit knob has two functions: prevent the
contact between slide and objective and acts as
"focus memory".
1. After focussing the specimen, pull the lever ①
toward the front of the microscope and lock it.
(Fig. 32).
• In this way the focus upper limit is set.
2. Now one can lower the stage with coarse focus
knob, replace the specimen and raise again the
stage up to the upper limit: specimen will be in
approximate focus and will need a fine adjustment
to get the proper focus.
• Fine focus movement is not affected by the
coarse focus lock.
• To unlock, move the lever in the opposite
direction to the one used for the locking.
• Two stoppers ② are inserted on the frame. DO
NOT REMOVE THE TWO STOPPERS.
9.11

Centering the condenser

1. Place the specimen on the stage, insert 10x
objective into the light path and focus.
2. Insert the front lens of the swing-out condenser
①. (Fig. 33)
3. Rotate the field
counterclockwise direction, to fully close the
diaphragm.
4. Rotate the condenser height adjustment knob ③
to focus the edges of the diaphragm.
5. Rotate the two centering screws ④ to bring the
bright spot in the centre of the field of view.
6. Gradually open the diaphragm. The condenser is
centred when the diaphragm image is symmetrical
to the field of view. (Fig. 34)
7. In normal use, open the diaphragm until it
circumscribes the field of view.
9.12 Effects of the field diaphragm
Field diaphragm adjusts the illuminated area to obtain
a high contrast image.
Set the diaphragm according to the objective in use
until it circumscribes the field of view, in order to
eliminate unnecessary light to eyepieces.
diaphragm ring
②
②
③
in
①
②
Page 21
①
UNLOCK
LOCK
④
F ig. 32 F ig. 32
F ig. 33 F ig. 33
F ig. 34 F ig. 34