Detailed use of optical microscopes and steps of using oil immersion lenses!
(1) Access to the microscope
Hold the mirror arm with one hand, and support the mirror base with the other hand, and gently place the microscope on the table, about one thumb away from the edge of the table.
Adjust the chair to an appropriate height so that you can use the microscope with ease.
Take 95% alcohol and lens cleaning paper, and wipe all lenses clean (※Note: Wipe only in a single straight line).
Place the slide specimen on the stage stably, and clamp it with a slide clip (※ Note: Please confirm whether it is clamped well, so as not to cause the slide to jump up, causing injury to the students or damage to the microscope lens).
(2) Use of low magnification lens
Lower the stage to the lowest point first, and turn the rotating disk (Revolving nosepiece) so that the low power lens is directly below the lens barrel.
Turn on the light source, adjust the light source adjustment knob and the aperture (Iris diaphragm), so that the brightness in the field of view is appropriate.
Place the slides to be observed on the stage, clamp them with slide clamps, and turn the adjustment knobs (mechanical stage control knobs) to adjust the position of the slides. Turn the adjustment wheel (Adjustment knob) until the distance between the low power mirror and the stage is about 0.1 cm (or the stage can no longer be raised).
Observe through the eyepiece, and at the same time slowly turn the adjustment wheel (Adjustment knob) toward yourself to lower the stage until the image is clear. If the field of view is too bright or too dark, you can adjust the light source adjustment knob and the aperture (Iris diaphragm) to make the brightness in the field of view appropriate.
(3) Use of high magnification lenses
First use the low-power lens to find the target to be observed, and adjust the part to the center of the field of view. Repeat A.~D. of the "Use of low-magnification lens" method.
(4) Use of oil mirror
First use the high-power mirror to find the target to be observed, and adjust the part to the center of the field of view.
Turn the high-magnification lens away, add a small drop of oil immersion oil on the glass slide of the object image range (that is, the area illuminated by the light), and use a 100X objective lens (ie oil immersion objective), carefully immerse the oil immersion lens in the oil, readjust the aperture, and slowly turn the adjustment knob (Adjustment knob) until the image is clear.
(5) Precautions
It is strictly forbidden to pick up the microscope with one hand.
If it is necessary to move the microscope, be sure to lift the microscope and put it in an appropriate position. It is strictly forbidden to push the microscope (the vibration caused by the push may cause the internal parts of the microscope to loosen, remember!!), and please handle the microscope with care.
When using a microscope, the height of the chair should be appropriate. When observing, you should be used to observing with both eyes at the same time, and the aperture and brightness of the light source should be appropriate. Otherwise, you will easily feel tired when observing for a long time.
Be sure to lower the stage to the lowest point when turning the rotating disk, so as not to scratch the lens of the eyepiece due to improper operation.
For specimen staining or any other operation, the slide should be removed, and then put back on the stage for observation after the operation is completed. Do not operate on the stage to prevent dye or other liquids from flowing into the microscope or damaging the lens.
After observing one material, when you want to change another material, be sure to lower the stage to the lowest point, and then refocus according to the standard procedure after changing the slide. Do not directly replace the specimen, so as not to scratch the lens or slide specimen.
Before and after the microscope is used, all lenses should be cleaned with lens paper (Lens paper) and 95% Alcohol. When wiping, they should be wiped lightly in a single straight line, and should not be rotated and rubbed.
When wiping the microscope lens, only lens paper (Lens paper) can be used. Do not touch the lens with other paper or fingers.
After using the microscope, lower the stage to the lowest point, align the low-magnification lens with the round hole in the center of the stage, roll up the power cord, cover it with a dust cover, and store it in a storage cabinet.
If not used for a long time, all lenses should be cleaned with Xylene (Xylol).
4. Magnification & Microscopic Measurement
The approximate value of the magnification of the microscope is close to the product of the magnification of the eyepiece and the objective lens, but due to the difference in production, each lens has a slightly different error. To know the actual size of the observed object, first install an ocular micrometer (Ocular micrometer) between the two lenses of the eyepiece (as shown in Figure 2-1a). Put a stage micrometer (Stage micrometer) on the stage (as shown in Figure 2-1b). The micrometer is a straight line with 1 mm divided into 100 small divisions engraved on the glass slide, that is, the length of each small division on the stage micrometer is 0.01 mm (10mm). The method of use is: move the micrometer on the stage so that the scales at one end of the two micrometers overlap to form a straight line, and then check the overlap of the scales at the other end, and calculate the number of divisions on the two micrometers in this interval.
