Practical Tips & Precautions for Using a Microscope
① Focusing: Insert the stage plate into the stage mounting hole on the base. Use the frosted glass stage plate for transparent specimens and the black‑and‑white stage plate for opaque specimens. Loosen the locking screw on the focusing slide carriage, adjust the height of the main body to achieve a working distance roughly matching the magnification of the selected objective lens, and tighten the locking screw after adjustment. For focusing practice, flat objects such as printed paper, rulers or set squares are recommended.
Diopter adjustment: First set the diopter rings on both left and right eyepiece tubes to the zero graduation mark. Normally, observe through the right eyepiece first. Turn the zoom handwheel to the lowest magnification. Rotate the focusing knob and diopter ring to focus on the specimen until the image becomes sharp. Then switch the zoom handwheel to the highest magnification and adjust again for a clear image. Next, observe through the left eyepiece. If the image is blurred, axially adjust the diopter ring on the left eyepiece tube until the specimen image is sharp.
② Interpupillary distance adjustment: Swing the two eyepiece tubes to change the exit pupil distance. The interpupillary distance is set correctly when the two circular fields of view merge completely into one. Note that due to individual differences in vision and accommodation, separate parfocal adjustment is required for different users, or even for the same user at different times on the same stereomicroscope, to obtain optimal observation results.
Before replacing either the upper or lower light source bulb, turn off the power switch and unplug the power cord from the mains socket.
To replace the upper light bulb: Unscrew the knurled screws of the upper light housing, remove the housing, take out the faulty bulb from the socket, fit a new bulb, then reinstall the light housing and knurled screws.
To replace the lower light bulb: Remove the frosted glass stage plate or black‑and‑white stage plate from the base, take out the faulty bulb from the socket and install a new bulb, then refit the stage plate.
When replacing bulbs, wipe the glass envelope of the new bulb with a clean soft cloth or cotton gauze to guarantee good illumination.
