The objective heater is designed to mount onto oil immersion objectives. To eliminate the heatsink effect that is accelerated by the presence of oil or water as an optical coupling medium, these objectives have a retractable central tube which contains the optical elements. Heat is directly transferred to this tube and sensed by a thermistor which is part of an intelligent feedback control loop. The heater loop requires a minimum of 5mm longitudinal physical contact with the cylindrical objective surface. In some cases there may be a decorative collar or sleeve on the objective which must be removed in order to permit adequate surface contact for the heater loop.
Objectives are expensive and delicate.
We recommend following the directions below carefully. Although great care has been taken to produce a reliable product to control the temperature of your objective, there is always some risk. The user assumes all liability for any damage that may occur due to the use of this objective heater. The AC power line input, power switch, voltage selector, and fuses are all incorporated on the rear panel. The fuse carrier contains two 0.5A slow blow fuses.