How to use an optical microscope
1. Operation steps and precautions
(1) Upright Microscope
1. Hold the mirror arm with your right hand and the mirror base with your left hand to keep the mirror body upright. The desktop should be clean and stable, and you should choose a place near a window or with sufficient light. The single tube is generally placed on the left side, 3 to 4 cm away from the edge of the table.
2. Clean and check whether the microscope is faulty and clean. The mechanical parts of the mirror body can be wiped with a clean soft cloth. The lens should be wiped with lens cleaning paper. If there is glue or dirt, clean it with a small amount of xylene.
3. Raise the mirror barrel to a distance of 1 to 2 cm from the stage, and align the low-magnification mirror with the light hole. Adjust aperture and reflector, use flat mirror when light is strong, use concave mirror when light is weak, reflector will turn with both hands. If a microscope with a light source is used, this step can be omitted, but a knob for adjusting the brightness is required.
4. Install the specimen. Put the slide on the stage, and pay attention that the side with the cover glass must face up. Secure the slide with spring clips, and turn the knob of the stage mover so that the material to be observed is aligned with the center of the aperture.
5. When focusing, first turn the coarse focus knob to lower the lens barrel slowly, and observe carefully from the side until the objective lens is close to the slide specimen, then observe from the eyepiece with the left eye, and turn the coarse focus knob with the left hand to raise the lens barrel. Stop until the specimen image is clearly seen, and then use the fine focus knob to adjust it back to clear. Operation Note: Do not adjust the focus directly under a high-magnification lens; when the lens barrel is lowered, observe the distance between the lens barrel and the specimen from the side; know the critical value of the object distance. If you use a binocular microscope, if there is a difference in the diopter of the observer's eyes, you can use the diopter adjustment circle to adjust it. In addition, the binoculars can be relatively translated to adapt to the distance between the operator's eyes.
6. Observation If you use a monocular microscope, open your eyes naturally, observe the specimen with the left eye, record and draw with the right eye, and at the same time adjust the focus with the left hand to make the object image clear and move the specimen field of view. The right hand records and draws. During microscopic examination, the specimen should be moved in a certain direction until the entire specimen is observed, so as not to miss or repeat. Adjustment of light intensity: In general, the light for stained specimens should be strong, and the light for colorless or unstained specimens should be weak; the light for low-power observation should be weak, and the light for high-power observation should be strong. In addition to adjusting the reflector or light source, the adjustment of the iris aperture is also very important.
(1) Observation with a low-magnification lens When observing any specimen, a low-power lens must be used first, because it has a large field of view, and it is easy to find the target and determine the part to be observed.
(2) High magnification observation When turning from low magnification to high magnification, you only need to slightly adjust the fine focus knob to make the object image clear. Do not use the coarse focus knob when using a high magnification lens, as this can easily crush the coverslip and damage the lens. When turning the objective lens converter, do not use your fingers to directly push the objective lens. This will easily cause the optical axis of the objective lens to be deflected, and the screw thread of the converter will be damaged due to uneven force, and finally the converter will be scrapped.
(3) Observation of the oil lens First use the low power lens and the high power lens to move the inspected object to the center of the field of view, and then change the oil lens for observation. Before oil lens observation, the brightness of the microscope should be adjusted to the brightest, and the aperture should be fully opened. When using an oil lens, first drop a drop of cedar oil (lens oil) on the cover glass, then lower the lens barrel and observe carefully from the side until the oil lens is immersed in the cedar oil and is close to the slide specimen, then observe with the eyepiece, and use the fine adjustment The focus knob lifts the lens barrel until the focal length of the specimen is seen clearly and then stops and adjusted clearly. Cedar oil should be added in an appropriate amount. After using the oil lens, be sure to wipe off the cedar oil with a lens cleaning paper dipped in xylene, and then wipe off the excess xylene with a dry lens cleaning paper.
7. Finish the operation. After observing, remove the sample, reverse the converter, make the lens V-shaped to the sides, and the mirror should be erected. Lower the lens barrel, wipe it clean, and put on the lens cover. If you are using a microscope with a light source, you need to adjust the brightness knob to adjust the brightness to the darkest, and then turn off the power button to prevent the instantaneous excessive current from burning out the light source when you turn it on next time.
(2) Inverted Microscope The main difference between an inverted microscope and an upright microscope is that the objective lens is located below the stage, which is conducive to performing some real-time operations on the sample above during observation. The operation process of an inverted microscope is basically similar to that of a binocular upright microscope. The following points should be noted: the hinged binocular eyepieces can be adjusted to a comfortable position during observation. Splashes of tissue culture fluid or water onto the stage, objective, or microscope frame may damage the equipment. If spilled, immediately unplug the power cord from the wall outlet and wipe up the spilled liquid or water. Be sure to turn the light intensity knob gently and do not try to turn the knob past the end position. After use, be sure to adjust the intensity of the light to the minimum before turning off the power. After use, the three-hole converter should be rotated so that the objective lens is placed on the lower side of the stage to prevent dust from settling.
(3) Solid microscope is also called stereo microscope or dissecting microscope. The operation steps are basically similar to those of a binocular upright microscope: when using a dissecting mirror, you need to use both hands to move and keep steady. If the mirror box needs to be moved, the mirror box should be locked, and the key of the mirror box must be removed at the same time. If there is a dust cover on the mirror tube, it should be removed and replaced with the eyepiece and eyecup. Place the sample on a glass slide or in a wax dish and place it on a loading plate for observation. Tighten the screws, raise the mirror body to a certain height first, and then lock the mirror body. The eyepiece tube can be turned to fit the eye distance before observation. The difference in binocular vision can be adjusted by the visual circle. When focusing, do not turn the lifting screw too fast or forcibly, so as not to damage the gear. For magnified observation, turn the magnification dial until the required magnification. The larger the object image, the darker the light, so it is necessary to adjust the light source and select a good background object. After use, first take away the things on the loading tray, and tighten the elastic screws to put down the mirror body and lock it. Remove the eyepiece and replace the dust cover. Put the elements back together, being careful not to interchange with other mirrors. Wipe the mirror body clean with a cloth, put it into the mirror box, and lock the mirror box.
