Adjusting The Microscope - Leica M844 User Manual

Adjusting the microscope

Adjusting the illumination
Warning 12
Light which is too intensive can damage the retina.
➩Safeguard your patients:
short exposure times,
low brightness setting,
use protective filters (GG420 built in).
We recommend setting the minimal required light intensity for the
operation. Infants, small children, aphakic patients who have not
had their lenses replaced by artificial lenses with UV protection,
and persons with eye diseases are at higher risk. The risk is also
elevated if the person to be treated has been exposed to illumina-
tion from the same or a similar ophthalmological instrument with
an intense visible light source within the previous 24 hours. This
applies especially to patients that have been examined via retinal
photography.
The decision with regard to the light intensity to be used must be
made on a case-by-case basis. In any event, the surgeon must
evaluate the risks and benefits of the used light intensity.
Damage may occur despite all efforts to minimize the risk of
retinal injury by surgical microscopes. Photochemical retina
damage is a possible complication arising from the necessity to
use intense light to make eye structures visible during difficult
ophthalmological processes.
Adjusting the brightness
You can adjust the brightness of the active Main Light and the
OttoFlex II lamp using either the touch panel or the footswitch.
TM
Using the footswitch:
Depending on the functions assigned to the footswitch
(see page 16), you can switch the Main Light and OttoFlex
lamp on and off, and increase and decrease their brightness,
using the foot/handswitch.
Using the touch panel:
You can change the brightness for the active Main
Light and OttoFlex
or directly pressing the corresponding
brightness bar.
TM II lamp by pressing the "+" or "-" key
Leica M844 – Leica M820 / Ref. 10 713 294 / Version I
Clicking the "+" or "-" key changes the brightness value in
increments of one. Holding down the mouse button with
your finger changes the value in increments of five.
Setting the brightness of a lamp to zero switches it off.
The Leica M820 and Leica M844 are also equipped with
an additional second light source, called OttoFlex
The combined output of the two light sources is limited
electronically.
If you cannot increase the brightness of the desired
light source, first decrease the brightness of the other
light source; you are then able to increase the
brightness of the desired lamp.
Quick-change lamp mount
The main light has a quick-change lamp mount.
➩If a main lamp fails during the operation, simply switch over
to the second lamp.
➩Activate the second lamp by moving the quick-change lamp
mount on the underside of the optics carrier.
The yellow "Check" button appears on the control unit.
If you click the button, the informational message
"Check Main Light 1 (or 2)" is displayed.
➩Replace the defective bulb after the operation
(see page 59).
Filters
There are two slots (62) in the microscope housing into which
filter slides can be inserted.
Left filter slot:
Right filter slot:
TM II
The plane of filter is sharply imaged in the same plane as the
object.
The GG420 UV protection filter is built-in. In addition, the GG475
UV protection filter is available.
➩Remove the filter cover.
➩Push in the filter slide, inclined slightly upwards, until it
engages.
Inserting a filter automatically deactivates the
OttoFlex
the brightness bar for the OttoFlex
back to zero, and the caption changes to "Filter active".
If a slit lamp is active, it is not switched off if a
filter slide is inserted.
After the filter has been removed, the OttoFlex
switched back on using the hand/footswitch or at the control
unit.
Color filter, cobalt filter
Special filters or diaphragms.
TM II lamp. On the control unit (main menu),
TM
Use
TM II.
II lamp goes
TM II lamp can be
39