Functions
16
PROVIDO Ref. 10732418 / Version 03
PROVIDO Ref. 10732418 / Version 03 17
5.3 Illumination
The main illumination of the PROVIDO is a xenon lamp and is
located in the stand. Illumination is routed to the optics carrier via
fibre optic light guide.
The backup lamp can be either another xenon lamp or a LED lamp.
In case of a failure of the lamp in use, the other lamp can be
selected manually with the sliding switch below the horizontal arm
(see page 21).
5.3.1 AutoIris
AutoIris synchronizes the illumination field automatically according
to the magnification factor.
Using the manual override, the illumination field can be adjusted
manually.
5.3.2 BrightCare Plus
BrightCare Plus is a safety function which automatically limits the
maximum brightness depending on the working distance.
Excessively bright light can, in combination with a short working
distance, cause burns in patients.
When shipped from the factory, the "BrightCare Plus" safety
function is activated for all users.
Luminous energy
The optics of the PROVIDO have a variable working distance of
between 225 and 600 mm. For Xenon lamp 300 W the system is
designed in such a way that it delivers sufficient light to produce a
bright image even at a long working distance of 600 mm.
In accordance with the formula Ev=Iv/d
2
, the light quantity
continually increases by 710 % when the working distance is
changed from 600 to 225 mm.
(Ev = light intensity, Iv= brightness, d= distance from light
source).
This means that less light is required to work with the microscope
at a shorter distance than at a greater distance.
It is advisable to begin with a low light intensity and
increase it until an optimum level of illumination is
achieved.
Heat release
Heat from non-visible light (over 700 nm) is filtered out of the light
from the used xenon light source. Nevertheless, white light also
always develops heat. An excessive amount of white light can lead
to overheating of tissue and metal objects.
It is advisable to begin with a low light intensity and
increase it until an optimum level of illumination is
achieved.
BrightCare Plus display
When BrightCare Plus is activated, the red line on the brightness
adjustment bar shows the maximum adjustable brightness for the
current working distance.
The brightness cannot be set to a level beyond the red line unless
the BrightCare Plus function is intentionally deactivated.
When the working distance is reduced too much at a set brightness,
the brightness is reduced automatically.
5.4 Leica FusionOptics
This feature provides an augmentation in resolution and depth of
field for an ideal 3-D optical image.
Leica FusionOptics operates with two separate beam paths with
different information: the left beam path is optimized for high
resolution, the right beam path for optimum depth of field.
The human brain merges these two very different images to a
single, optimal spatial image.
