The debugging of a biological microscope directly affects the imaging quality and observation efficiency, and requires a systematic operating procedure to be followed. The key debugging details are analyzed from three dimensions: preliminary preparation, optical system calibration, and functional verification.

1、 Standard preparation before startup

The placement environment should be kept away from vibration sources, and the workbench should be kept level and stable. Before connecting the power supply, check the voltage compatibility and confirm that the anti slip rubber pad on the base is firmly pressed. Before turning on the light source, a filter should be installed to protect the eyes from strong light stimulation. The stage needs to be wiped clean, and when adding mirror oil, a special oil-based pen should be used to mark the area to prevent sample contamination.

2、 Accurate calibration of optical systems

Positioning of objective lens converter: Rotate the converter to allow the low magnification objective lens to enter the optical path, and stop after hearing a crisp engagement sound. Observe the field of view through the eyepiece. If there is a significant deviation, loosen the fixing screw of the converter for fine adjustment to ensure that the concentricity error of each objective lens is less than 0.5mm.

Spotlight adjustment: Using Kohler lighting method, raise and lower the spotlight until the field of view brightness is uniform and there are no dark corners. Adjust the diameter of the iris aperture to match the numerical aperture of the objective lens, usually controlled at 80% of the back focal plane of the objective lens.

Eyepiece diopter compensation: When both eyes are open for observation, rotate the left and right eyepiece tubes separately until the two images overlap. When changing observers, it is necessary to readjust to avoid misjudgment caused by visual fatigue.

3、 Optimization steps for microscopic imaging

Specimen focusing technique: First, use a low-power microscope to find the target area and move the desired observation site to the center of the field of view. When converting to a high-power lens, do not directly rotate the coarse focus screw. Instead, lift the objective lens to avoid crushing the glass slide, and then slowly lower it to approach the focal plane. Fine focusing uses a fine pitch spiral with a micro grid value of 0.002mm/turn.

Resolution verification: Place the resolution test board and select the standard pattern group corresponding to the objective lens. If the minimum engraved line cannot be clearly distinguished, it is necessary to check whether there are stains on the front lens of the objective lens, or adjust the height of the spotlight to enhance the depth of field.

Color difference correction: When observing color samples, if there is a purple edge phenomenon, the iris aperture can be appropriately reduced; The yellow edge requires an increase in aperture diameter. It is recommended to use a flat field achromatic objective lens for special staining samples.

4、 Functional testing items

Mechanical stability test: Repeatedly switch different magnification objective lenses and observe whether the stage undergoes displacement. Qualified equipment should have a target position offset of no more than 5% of the field of view radius after 10 consecutive switches.

Light source uniformity verification: Remove the specimen and observe the brightness distribution of the empty field of view. A high-quality microscope should present a uniform gray white background without obvious bright spots or dark areas.

Confocal inspection: Focus on the same specimen under different objective lenses and record the clear focal plane of each objective lens. The focusing error of standard equipment should be controlled within ± 5 μ m.

5、 Key points of daily maintenance

After each use, use lens cleaning paper to wipe the front plate of the objective lens in one direction, and it is strictly prohibited to rub back and forth to damage the coating. Add clock lubricating oil to mechanical components every quarter, and apply molybdenum disulfide lubricant to the surface of the guide rail. When idle for a long time, the lithium battery in the battery compartment should be removed and powered on for dehumidification once a month.