Leica DMLB Bedienungsanleitung Seite 69

Changing the halogen lamp in the illumination
unit
Attention!
Disconnect from power supply.
Screw out the Allen screw at the back and
remove the lamp unit from the lamphousing.
Take the lamp out of the socket and replace,
making sure that the contact paths of the lamp
(6 V 4 W) lie on the contacts in the socket.
Do not touch the lamp bulb with your fingers due
to the danger of perspiration burning in.
After the lamp unit has been replaced in the
lamphousing, the lamp holder can be adjusted
vertically by about 2 mm with the Allen screw
from beneath.
Looking through the microscope eyepiece,
adjust the lamp to the height where the greatest
image brightness is achieved.
Operation of diapositive overlay
The diapositive overlay device (Fig. 49) is used
to reflect measurement and comparison masks,
µm marks, marker arrow, company logo, charge
and quality data, etc. into the microscope image
so that they can be recorded together with the
image.
The following diapositives are available:
Marker arrow
10 mm measurement scale with 100 divisions
µm marks for 2.5x – 100x objectives
10 x 10 mm grid division in 100 fields
Test circle and measured length for grain size
measurements
Picture series for ASTM-E 112 grain size
measurements.
Individual masks with any measurement and
comparison patterns, quality data, company
logos etc. can be made by the user.
To do this, the original must be photographically
reproduced on a 35 mm negative, i.e. bright lines
on a dark background and framed in a standard
50 x 50 mm slide frame. The best film to use is
fine-grain "document film".
The diapositive is imaged in the intermediate
image plane of the microscope at a scale of 2 : 1.
A distance of e.g. 5 mm in the diapositive overlay
is magnified to 10 mm in the intermediate image
plane of the microscope.
The overlay device only works when the
beamsplitter in the tube (46.4) is set at 50/50
(switch rod in middle position).
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