Centring of the lamp When using the

Centring of the lamp When using the reflected light unit for a long time, the lamp holder possibly moves out of its centre due to the heat development. In this case the illumination is no longer efficiently adjusted. This circumstance can be identified by the user when the background brightness of the field of view has an uneven distribution. This malposition can be corrected by performing the following method. 1. Make sure, that the lamp housing has cooled down. 2. Switch on the reflected light unit. 3. Choose the objective with the lowest magnification for the beam path. 4. Remove all the (filter) slides from the beam path. 5. If there is one, remove the object (slide) from the stage. 6. Remove one of the eyepieces from the tube. 7. While watching through the tube connector, close the aperture diaphragm of the reflected light unit, so that its border can be seen clearly. 8. The decentred image of the lamp filament can now be seen as well. 9. Loosen the rotary knob on the rear of the lamp housing, so that you can move it together with the attached lamp holder. 10.Look through the tube connector and move the rotary knob in order to bring the image of the lamp filament back to the centre of the opening of the aperture diaphragm. 11.Fixate the rotary knob again.