Use Of The Bertrand Lens; Use Of Diffusing Filter (B-1000Pol-I) - Optika Italy B-1000 Serie Manual De Instrucciones

12.6

Use of the Bertrand lens

Bertrand lens allows observation in Orthoscopy and
Conoscopy.
In the disengaged position ("O") the lens allows
observation in Orthoscopy, while in the engaged
position ("B") it is possible to make observations in
Conoscopy.
1. Rotate the upper knurled ring of the Bertrand lens
① to engage the "B" position. (Fig. 53)
2. Using one objective from 20x to 60x, focus the
conoscopic image using the focus ring ②.
3. If the conoscopic image is not perfectly centred
with respect to the optical axis, centre the image
using the centering screws.
• By turning the stage you will see black fringes
that will appear and disappear depending on
the rotation of the stage. These fringes are the
crystallization axes of that specific crystal. (Fig.
54)
12.7 Use of diffusing filter (B-1000POL-I)
Depending on the type of sample to be observed, it
may be useful to remove or insert the diffusing filter
④ that is present in the back of the illuminator.
1. Insert the slide into the illuminator until it reaches
the end of its stroke to insert the diffuser filter in
the optical path. (Fig. 55)
2. Pull out one click (until the first "click") the slide to
remove the filter from the optical path, but always
leaving the slide in place.
3. If you intend to completely remove the slide from
the illuminator, remove it completely from its
housing.
①
Page 31
③
F F ig. 53 ig. 53
②
F ig. 54 F ig. 54
④
F ig. 55 F ig. 55