Objective
Cooling Collar
The Objective Cooling Collar is an attachment to an objective
that provides an isolated pathway through which a refrigerated
fluid can flow. this provides an efficient means of cooling the
objective. The source of the chilled fluid can be as simple as
a dewar of ice water or as sophisticated as an AC powered chiller
bath. The removal of heat from the objective is more difficult
than heating because you are limited by the thermal transfer
efficiency of both the objective and the contact surface of the
cooling ring. Therefore, the cooling ring needs to be of sufficient
size to work. It is advisable to make sure you have enough room
under the stage for the additional diameter required for the
cooling collar and tubing. Cooling collars are precision machined
to fit specific objectives.
Objective Thermal Isolator & Spacer
It
is necessary to use a thermal isolator to both prevent heat
from the nosepiece from entering the objective and to prevent
condensation from forming on the lower element. The Bioptechs'
Thermal Isolator mounts between the objective and nosepiece
and is made of a material having a low thermal conductivity.
It also contains a two sided AR coated window and gas ports
through which dry air is pumped to prevent condensation. It
is necessary to provide a supply of dry air into the base of
the Thermal Isolator. The Thermal Isolator will add 9mm to
the height of the objective. Therefore, it is necessary to
elevate the stage by the same amount. Bioptechs provides spacers
for stage mounts on special order. When the height of a microscope
stage is modified to accommodate the addition of a Thermal
Spacer to one of the objectives, it is recommended to add spacers
to the other objectives on the turret as well.
Note: When ordering an 8mm
Objective Spacers you must specify the thread type:
RMS = 0.8" x 36 tpi = (approximately
20 mm diameter)
25mm x 0.75 mm/thread = (approximately 1" diameter)
| Comparison
of the effect of the use of a Thermal Isolator or
Spacer. |
60x
objective without thermal
isolator |
60x objective with thermal isolator |
Notice
the difference in temperatures of the nosepiece shown
above. The objective without the thermal spacer (top)
is transferring of heat to the nosepiece. Therefore,
more energy has to be applied to compensate for the
heat loss as demonstrated by the elevated temperature
of the heating band. Although it is possible to overcome
the heat loss with more power, it is not recommended
due to the possibility of damage to the objective and
the fact that the temperature regulation will become
more labored.
However, the objective with a thermal spacer (bottom) demonstrates very little
heat loss to the nosepiece and the heater-band is obviously cooler. With less
continual heat drain, less energy is required to establish and maintain temperature.
Also notice how efficient the objective heater is transfering heat to the objective,
you can see the band is significantly cooler. This means there is no excess heat
being radiated from the objective heater band. |
|
Stage Spacer
Kit
This
kit provides the necessary hardware to accurately raise the
height of a stage 8mm. The kit consists of: (4) 8mm high machined
stage spacers (4) 5mm x 25mm allen bolts This kit was designed
for the 8mm Thermal Spacer, designated with a groove in the
sidewall of the spacer itself. (see picture below) 8mm Stage
Spacer Kit Part #: 19-19-01
8mm Objective Spacer
The Thermal
Spacer has a groove around its side-wall to distinguish it
from the 9mm version used for Thermal Isolators. It's only
purpose is to thermally isolate the nosepiece of the microscope.
It does not have or need gas ports or a window. It will enhance
the thermal transfer efficiency of the objective.
Note: When
ordering an 8mm Objective Spacers
you must specify the thread type:
RMS = 0.8" x 36 tpi = (approximately 20 mm diameter)
25mm x 0.75 mm/thread = (approximately 1" diameter)
Objective Wrench & Plier
Set
In order to expose sufficient
surface for mounting heat transfer devices on some manufacturers'
objectives, it is necessary to remove the outer decorative
collar which contains written information such as magnification,
N.A., etc. The objective wrench is designed to enable the user
to isolate the mechanical stress applied to an objective when
removing this collar.
The rotational force applied to the objective
must be applied exclusively to the mounting threads and the
cover. The wrench is designed with two thread sizes (0.8" x
36 TPI (RMS) and 25mm x 0.75 mm/thread). It will enable the
user to securely bind these threads and provide sufficient
leverage for removal of the cover.
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