Oil immersion lens

Definition

An oil immersion lens is a type of objective lens used in microscopy that requires a drop of oil between the lens and the cover slip to achieve high magnification and resolution. It is typically used to view very small specimens like bacteria.

5 Must Know Facts For Your Next Test

1. Oil immersion lenses usually have magnifications of 100x or higher.
2. The oil used has a similar refractive index to glass, reducing light refraction and increasing resolution.
3. Proper use of an oil immersion lens can distinguish details as small as 0.2 micrometers.
4. Common oils used include cedarwood oil and synthetic immersion oils.
5. When using an oil immersion lens, it is important to clean the lens immediately after use to prevent damage.

Review Questions

• Why is oil used with an oil immersion lens?
• What magnification levels are typical for oil immersion lenses?
• How does the refractive index of the immersion oil affect image resolution?

Related terms

Objective Lens: A component of a microscope that gathers light from the sample and focuses it to create an image.

Refractive Index: A measure of how much light bends when it enters a material from another medium.

Resolution: The ability of a microscope to distinguish two close objects as separate entities.