OM Microscope Immersion Oil

Microscope Immersion Oil is a transparent optical liquid used with high-power oil-immersion microscope objectives, especially 100× objectives, to improve image brightness, resolution and clarity. The oil fills the air gap between the microscope slide or coverslip and the objective lens, reducing light refraction and allowing more light to enter the objective. Standard microscopy immersion oils are formulated with a refractive index close to that of optical glass, typically around 1.515–1.518, depending on the manufacturer and formulation.