How to use and protect optical microscope oil lenses
Due to the small size of bacteria, in morphological studies of bacteria, it is often necessary to use a microscope oil lens to observe them more clearly. Therefore, students must be proficient in the use and protection of oil lenses.
Identification of oil lens:
The magnification of each objective lens can be identified by its appearance. The greater the length of the lens and the smaller the diameter of the lens, the greater the magnification; conversely, the smaller the magnification. The length of the oil lens is longer than that of the low and high power lenses. The lower edge of the lens is usually engraved with a circle of black or white lines and the words 100×, 1.25 or oil.
How to use oil lens:
1. When using a microscope oil lens, the microscope must be upright on the table. The arms must not be bent to tilt the stage to prevent the cedar oil from overflowing, affecting observation and contaminating the table.
2. Aiming at the light:
When using natural light as the light source, a flat reflector should be used; if artificial light is used, a concave mirror should be used. First open the aperture and turn the reflector to concentrate the light on the collector. Move the collector up or down and zoom the aperture as needed to achieve optimal light intensity. Generally, when observing objects with a low-magnification or high-magnification lens or examining unstained specimens with an oil lens, the light collector needs to be lowered and the aperture appropriately narrowed to weaken the luminosity; if an oil lens is used to examine stained specimens, the luminosity should be strong. The microscope brightness switch should be adjusted to the brightest setting, the aperture should be fully opened, and the light collector should be raised to be level with the stage.
3. Adjust focus:
(1) Place the specimen piece on the stage, fix it with the specimen pusher, and move the part to be examined under the objective lens. First use a low-power lens to find the position of the specimen, then raise the lens tube, put a drop of lens oil on the area of the specimen to be inspected, and then change the oil lens for observation.
(2) Turn the coarse adjuster to slowly raise the stage (or gradually lower the lens barrel) until the oil lens is immersed in the oil. At this time, the eyes should be viewed from the side to avoid crushing the specimen and damaging the lens.
(3) Then move your eyes to the eyepiece, while observing from the eyepiece, slowly turn the coarse adjuster in the opposite direction (lower the stage, or raise the lens tube). When blurry objects appear, switch to the fine adjuster and turn Until the object image is clear.
(4) After the observation is completed, the lens barrel should be raised first, and the oil lens should be twisted to one side, and then the specimen piece should be removed. After using an oil lens, you should immediately wipe off the oil on the lens with lens cleaning paper. If the lens oil is sticky and has dried on the lens, you can use lens cleaning paper dipped in a little xylene to wipe the lens, and then wipe off the remaining xylene with dry lens paper to prevent xylene from penetrating and dissolving the glue used to fix the lens. , causing the lens to shift or fall off.
