Calibration and Operation of the Stereomicroscope
Focus Adjustment
Insert the stage plate into the stage plate mounting hole on the base. Use a frosted glass plate for transparent specimens and a black-and-white plate for opaque specimens. Loosen the locking screw on the focusing slide holder, and adjust the height of the microscope body to achieve a working distance matching the magnification of the selected objective lens. Tighten the locking screw after adjustment. A flat object such as printed paper, a straightedge or a set square is recommended for focusing.
Diopter Adjustment
First, set the diopter rings on both the left and right eyepiece tubes to the zero mark. Normally, observe through the right eyepiece tube first. Turn the zoom knob to the low magnification position. Adjust the focusing handwheel and diopter ring until the specimen image is sharp. Then switch the zoom knob to the high magnification position and adjust again to obtain a clear image. Next, observe through the left eyepiece tube. If the image is blurred, axially adjust the diopter ring on the left eyepiece tube until the image becomes clear.
Interpupillary Distance Adjustment
Swing the two eyepiece tubes to change the exit pupil distance. The interpupillary distance is correctly set when the two circular fields of view fully merge into one. Note that due to individual differences in vision and ocular accommodation, separate parfocal adjustment is required for different users, or for the same user at different times, to achieve optimal viewing results.
Bulb Replacement
Before replacing either the upper or lower light source bulb, turn off the power switch and unplug the power cord from the socket. For the upper light source bulb: Unscrew the knurled screws of the upper light housing, remove the housing, take out the faulty bulb from the socket and install a new bulb. Refit the housing and knurled screws. For the lower light source bulb: Remove the frosted glass plate or black-and-white plate from the base, replace the faulty bulb with a new one, then reinstall the stage plate. Wipe the bulb glass shell with a clean soft cloth or cotton gauze during replacement to guarantee good illumination.
