Transmission electron microscopes are optical instruments, especially the imported transmission electron microscopes used in scientific research laboratories that do not move from tens of thousands to hundreds of thousands of yuan. Some company salespersons claim that their objective lens is more valuable than a car. Therefore, you must be careful when using it. Pay special attention to the following aspects.
(1) The working distance from low magnification lens to high magnification lens is long to observe the low magnification lens. After confirming the field of view, when turning to the high magnification objective lens, be sure to look carefully from the side. At this time, the working distance of the high magnification lens is often too small. If it collides with the stage or the glass slide, if you use too much force, it is very easy to damage the lens. For this kind of operation, you can first lower the stage, switch the objective lens, and then use the fine adjustment to adjust the focus vertically.
(2) The working distance of the oil lens to observe the oil lens is very short, generally within 0.2mm, so you must be especially careful when using the oil immersion objective lens. Be sure to use fine adjustment to adjust the focus, otherwise it is very easy to accidentally crush the glass slide. Crushing the film is not a big problem, but you will be miserable if the glass ballast damages the objective lens!
(3) Non-oil lens observation oil lens is more tightly sealed because oil is considered in the design; but for the objective lens that is not oil lens, the degree of airtightness is not so good. So when you use the oil lens and switch to other objectives, the objective lens will easily touch the oil on the glass slide, especially the high-power lens adjacent to the oil lens, such as 40x. Oil in the objective lens is very troublesome and almost impossible to handle. Even after returning to the factory, the objective lens is completely disassembled and cleaned again. The company may have to charge you for a new objective lens!
(4) For cleaning, use a cotton swab dipped in ether and alcohol mixture (7:3) to draw a circle from the inside to the outside of the lens center. Note: The cotton should be wrapped well, and never let hard sticks touch the surface of the lens; the cotton should be replaced once it is used to prevent small sand particles from scratching the coating on the lens surface; the principle of wiping the lens is: rather than wipe it clean. Don't wipe it; if it doesn't work, you can still ask someone from the company to wipe it!
