What is the principle of oil lens in optical microscope? Oil lens should be used to observe microorganisms
Oil lens, one of the optical microscopes, when used, the lens is immersed in oil (usually cedar oil), used to observe finer structures, is one of the commonly used microscopes in the laboratory, the clarity is slightly higher than ordinary optical microscopes, used for Observing chlamydia, bacteria, organelles, etc. The lens of the oil lens is small, and the light passes between the glass slide and the oil lens...
A microscope with a magnification of 100 times is an oil lens. When it is in use, it is necessary to drop cedar oil on the glass slide to see the object under the microscope clearly.
When using an oil lens, cedar oil needs to be dripped on the glass slide. This is because the magnification of the oil lens is high, and the lens is very small. When light passes through medium objects of different densities (glass → air → lens), part of the light will be refracted and lost, and the light entering the lens barrel is less and the field of view is wider Dark, objects cannot be seen clearly. For example, adding cedar oil (n=1.515), which is similar to the refractive index of glass (n=1.52), between the lens and the glass slide will increase the light entering the oil lens, enhance the brightness of the field of view, and make the object image clear.
Microorganisms are generally small, and when observed with an oil lens, the magnification is large and the observation is clearer!
Simply put, the refractive index of cedar oil is less than the refractive index of air, and light passing through small cells will have more access to the objective lens and be easier to observe.
