How to use a microscope lens with a focus spiral correctly?
Using a focus screw to adjust the focal length and find the object can be considered an important step in the use of a microscope. Never make the following errors during operation: first, focus directly under a high-power lens; The second is that regardless of whether the barrel rises or falls, the eyes always look into the eyeglass to see the field of view; The third reason is that the critical value of the object distance is not understood. When the object distance is adjusted to 2-3 centimeters, it is still upward, and the speed of rotating the quasi focal screw is very fast. The first two types of errors often cause the objective lens of the microscope to collide with the mounting, damaging the mounting or lens, while the third type of error is a common phenomenon among students when using the microscope. When adjusting the focal length, it is necessary to lower the lens at low magnification. First, rotate the coarse focus screw to slowly lower the lens barrel, and the objective lens should be close to the glass slide. However, be careful not to let the microscope lens and objective lens touch the glass slide. During this process, the eye should look at the objective lens from the side, then use the left eye to gaze into the objective lens, and slowly adjust the coarse focus screw in reverse to gradually raise the lens barrel until the object image is seen. At the same time, the object distance of a general microscope is about 1 centimeter. Therefore, if the object distance has exceeded 1 centimeter but the object image is still not seen, it may be that the specimen is not in the field of view or the coarse focus screw rotation speed is too fast. At this time, the mounting position should be adjusted, and then repeat the above steps. When blurry objects appear, it is necessary to switch to fine focus spiral adjustment. Only in this way can the search range be reduced and the speed of finding objects be improved.
How to convert a microscope lens to an objective lens?
After using a low magnification lens, switch to a high magnification lens. Do not use your fingers to directly rotate the microscope lens objective lens. This can easily cause the optical axis of the objective lens to deviate. The reason is that the material of the converter is soft, with high accuracy, and the thread of the microscope lens is uneven and easily loosened. Once the thread is damaged, the entire converter will be scrapped. Correctly operate the lower rotating plate of the control room's handheld converter to convert the objective lens.
