Common Failures and Remedies for Stereoscopic Microscopes
Focusing: Insert the work stage into the stage mounting hole on the base. Use a frosted glass stage for observing transparent specimens and a black-and-white stage for opaque specimens. Loosen the locking screw on the focusing slide, and adjust the height of the lens body to match the working distance corresponding roughly to the magnification of the selected objective lens. Tighten the locking screw after adjustment. For focusing, it is recommended to use a flat object such as flat printed paper, a ruler or a set square. Diopter adjustment: First turn 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. Rotate the focusing knob and diopter adjustment ring to focus on the specimen until the image becomes clear. Then switch the zoom knob to the high-magnification position and adjust again until the specimen image is sharp. 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 is clear.
Stereomicroscopes have a wide range of applications in industry, agriculture and scientific research due to their many advantages. Minor faults occurring during operation can be resolved on site according to actual conditions. Common faults are listed below: Blurry or dirty field of view: Possible causes include contamination on the specimen, eyepiece surface, objective lens surface or work stage surface. Solution: Clean the specimen, eyepiece, objective lens and work stage as needed.
Dual images cannot overlap: This may result from incorrect interpupillary distance adjustment. Correct the interpupillary distance. Misaligned dual images may also be caused by improper diopter adjustment; readjust the diopters. Another possible reason is mismatched magnification of the left and right eyepieces. Inspect the eyepieces and reinstall eyepieces of identical magnification.
Unclear image: Contamination on the objective lens surface is a likely cause. Clean the objective lens. Blurred image during zooming: Usually caused by incorrect diopter setting or improper focusing. Readjust the diopter and refocus.
Frequent bulb burnout or flickering illumination: Possible reasons include excessive local mains voltage, a failing bulb or poor wiring connections. Carefully check the supply voltage and confirm secure wiring connections of the microscope. If the bulb is near the end of its service life, replace it with a new one.
The pre-use calibration procedures for a stereomicroscope mainly include focusing, diopter adjustment, interpupillary distance adjustment and bulb replacement, which are explained separately below.
