What is the difference between oil immersion lens and ordinary objective lens in terms of usage?
When using an oil lens, a drop of tar needs to be dropped on the glass slide, and the objective lens cannot detach from the oil drop during the ascent process. Moreover, the magnification of the oil lens is larger than that of a regular objective lens.
When using oil mirrors, attention should be paid to:
1. After using the oil lens, first use a lens cleaning paper dipped in a small amount of xylene to wipe off the cedar oil on the lens and specimen, and then use dry lens cleaning paper to clean them. After adding tar, the field of view noticeably darkens. It is necessary to raise the light collector to the highest position and open the aperture to the maximum. Before using the oil mirror, the target observed by the low-power and high-power lenses must be in the center of the field of view.
2. Cypress oil is a specialized oil for oil mirrors. Dropping a liquid with a refractive index of 1.5 under a 100x oil mirror can significantly increase the resolution of the oil mirror and improve the observation effect of the microscope. Cypress oil has a refractive index of 1.52, making it an excellent oil for microscope oil mirrors.
3. When using a microscope oil mirror, the microscope must be upright on the table, and the mirror arm must not be bent, causing the stage to tilt, in order to avoid the overflow of asphalt, affecting observation, and contaminating the table.
The principle of using oil mirrors
The principle of using an oil mirror: When using an oil mirror, it is necessary to drip tar onto a glass slide. This is because the magnification of the oil mirror is high, while the lens is small. When light passes through medium objects of different densities (glass slide → air → lens), some of the light will refract and dissipate, resulting in less light entering the barrel and a darker field of view, making it difficult to observe objects clearly. If cedarwood oil with a refractive index similar to glass is dropped between the lens and the glass slide, it will increase the amount of light entering the oil mirror, enhance the brightness of the field of view, and make the object clear.
Oil mirror is one of the commonly used microscopes in laboratories, with slightly higher clarity than ordinary optical microscopes, used to observe finer structures such as chlamydia, bacteria, organelles, etc.
