In microscopy, magnification refers to the enlargement of the object being studied, while resolving power pertains to the capacity of an optical medium, such as a lens, to distinguish between proximate objects as distinct images.
The quality and usefulness of a microscope rely more on resolving power rather than on magnification. A microscope is an optical device used in viewing and studying objects that are not visible to the naked eye. The basic parts of a simple type of microscope, called a compound microscope, include the eyepiece, ocular lens, objective lens, revolving nosepiece, stage, condenser, condenser adjustment control, light source, light switch control and adjustment knobs.
One of the fundamental features of a microscope is its ability to augment images. One way to change the refractive index is by staining the specimen. Another is to use immersion oil. While we want light to refract differently between the specimen and the medium, we do not want to lose any light rays, as this would decrease the resolution of the image. By placing immersion oil between the glass slide and the oil immersion lens X , the light rays at the highest magnification can be retained.
Immersion oil has the same refractive index as glass so the oil becomes part of the optics of the microscope. Without the oil the light rays are refracted as they enter the air between the slide and the lens and the objective lens would have to be increased in diameter in order to capture them. Using oil has the same effect as increasing the objective diameter therefore improving the resolving power of the lens.
Resolution is the shortest distance between two points that can still be visually distinguished as separate. Using a microscope decreases the resolution to distances as short as 0. Resolution is a property of the eye.
Resolving power is the ability of a lens to show two adjacent objects as discrete. Resolving power is a property of a lens. Each lens in a microscope has a numerical aperture , or NA, value. This has to do with the angles of light that enter and exit a lens.
Its applications are beyond the scope of this lab, but numerical aperture does influence the resolution possible with a particular lens, and so the NA value for the lens is usually printed on each objective.
It will be a number less than 1. Each lens in a microscope also has a magnifying factor. This is the degree to which that lens magnifies an image.
It will be a number larger than 1. For instance a 10x objective magnifies the image ten-fold.
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