What makes the conventional objective lens different from the oil lens in terms of use?
The oil lens is different from the ordinary objective lens in the use method.
When the oil lens is in use, a drop of cedar oil needs to be dropped on the slide glass, and the objective lens cannot be separated from the oil drop during the rising process, and the magnification of the oil lens is larger than that of the ordinary objective lens.
When using oil mirrors, you should pay attention to:
1. After the oil lens is used, first wipe off the cedar oil on the lens and the specimen with a lens cleaning paper dipped in a little xylene, and then wipe it clean with a dry lens tissue. After adding cedar oil, the field of view becomes obviously darker, so the collector needs to be raised to the highest position, and the aperture should be opened to the maximum. Before using the oil lens, the target observed by the low-power lens and the high-power lens must be in the center of the field of view.
2. Cedar oil is a special oil for oil mirrors. Dropping a liquid with a refractive index of 1.5 under the 100 times oil mirror can significantly increase the resolution of the oil mirror and improve the observation effect of the microscope. The refractive index of cedar oil is 1.52, which is the best Good microscope oil immersion oil.
3. When using the microscope oil lens, the microscope must be upright on the table, and the arm of the microscope must not be bent to make the stage tilt, so as to avoid the cedar oil from overflowing, affecting the observation and polluting the table.
The principle of adding cedar oil to microscope oil lens
Cedar oil is a colorless or yellowish slightly viscous liquid. It is an aromatic oil obtained by distilling cedar wood, which contains olein and cedarol, and can be used as fragrance and microscope oil.
Because the magnification of the oil lens is high, and the lens is small, when light passes through medium objects of different densities (slide → air → lens), part of the light will be refracted and lost. Objects cannot be seen clearly.
If cedar oil (n=1.515), which is similar to the refractive index of glass (n=1.52), is added between the lens and the glass, the light entering the oil lens will increase, the brightness of the field of view will be enhanced, and the object image will be clear.
