What is immersion oil and why is it used?

Immersion oil is a type of oil that is used in microscopy to improve the resolution and clarity of the image. It is typically used with high-powered objective lenses, such as 40x or 100x, in light microscopes. When light passes through different mediums, such as air and glass, it can be refracted or bent, causing a loss of resolution and clarity in the image. Immersion oil has a similar refractive index to glass, which helps to reduce this refraction and increase the resolution of the image.

Immersion oil is typically applied directly to the specimen slide and the front lens of the objective lens. It forms a continuous bridge between the lens and the specimen, reducing the loss of light and improving the resolution and clarity of the image. It is important to use the correct type of immersion oil with the corresponding objective lens to ensure optimal results.

In summary, immersion oil is used in microscopy to improve the resolution and clarity of the image by reducing refraction and loss of light. It is an essential tool for obtaining high-quality images in high-powered microscopy.