3 ways to use a regular microscope
1. Low magnification observation
First, fix the position of the low magnification objective lens, then place the specimen slide, rotate the reflector, adjust the light, raise the objective lens, lower it to see the specimen, and then fine tune it to align with the focal length for observation. Except for a few microscopes, the position of the spotlight should be placed at the highest point. If an image of an external object appears in the field of view, the spotlight can be lowered slightly to make the image disappear. The iris aperture under the spotlight should be adjusted to an appropriate size to control the amount of incoming light and increase the brightness difference.
2. High magnification observation
The design of microscopes is generally confocal. After aligning the low-power mirror with the focus, switching to the high-power mirror basically aligns with the focus, as long as it is slightly rotated and fine tuned. Some simple microscopes are not confocal or cannot achieve confocal due to the replacement of the objective lens. Therefore, it is necessary to lower the high-power objective lens and then adjust the focus upwards. The iris aperture should be enlarged to form a sufficient cone angle. Move the spotlight up and down slightly to observe if the image is clear.
3. Oil immersed mirror observation
The working distance of oil immersed mirrors is very small, so it is necessary to prevent damage to the lens on the carrier and objective lens. When used, it is usually through low magnification, high magnification to oil immersed mirrors. After aligning the high-power objective lens with the specimen, add oil and immerse the lens for observation. The slide specimen can also be observed directly with an oil immersion microscope without going through low and high magnification objectives. If the microscope has an automatic descent stop device, after adding oil to the glass slide, move the oil immersed mirror down into the oil droplet until it stops descending, and then use fine adjustment to align the focus upwards. For those without an automatic lowering device, the method of aligning the focus is to observe from the side of the microscope, move the oil immersion mirror down to slightly contact the glass slide, and then use fine-tuning to raise the alignment focus upwards.
When using oil immersed mirrors, the mirror platform should be kept level to prevent oil flow.
The oil used in the oil immersion mirror should be clean, and the spotlight should be raised to the highest point and the iris aperture under the spotlight should be enlarged, otherwise it will reduce the numerical aperture and affect the resolution. Whether observing with an oil immersion mirror or a high magnification mirror, it is advisable to use an adjustable microscope lamp as the light source.
