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the maximum useful magnification for a light microscope is about

the maximum useful magnification for a light microscope is about


Answer: 1000X



Technically, the wavelength of light doesn’t limit magnification. It limits resolution. You can have magnifications that go far beyond the limits of resolution. In that situation, things would look larger, but you would not see any more detail.

Two factors limit resolution in a light microscope. The wavelength of light and the Numerical Aperture (NA) of the lens system (objective, condenser, etc.) The shortest visible wavelength is ~400 nm. The highest NA for a lens system to date is 1.4. This means the best resolving power on a microscope is ~200 nm. See the link below for formulae.

HIgh-end microscope manufacturers make 1.4 NA objectives in both a 60X and 100X oil (sometimes water) immersion objectives. If both the 60X and 100X objectives are 1.4 NA, both have the same resolving power at a given wavelength. Theoretically they could make a 200X 1.4 NA objective, but it wouldn’t have any more resolving power.

It is rare to see a microscope have an objective with a magnification higher than 100X (1000X total mag with a 10X ocular) simply because you wouldn’t see any more detail. But you could have higher mags if you wanted.

Because the wavelength of light would cause a distorted view if you tried to magnify too much. Oil immersion can help somewhat, but not enough for 1500x+,so Answer: 1000X .

Maximum magnification depends on the combination of lenses used, but it is usually 1000x. The thing is that magnification is only secondary factor when it comes to imaging. That is where the limit of resolution comes to play. It can be defined as the smallest length distinguishable by the microscope. Magnification beyond this limit of resolution possible, but you wont be able to see anything. This is called as empty magnification. Typically, the resolution of light microscopes are around 0.2 micrometers. You can see anything that has a dimension more than 0.2 micrometers, like cells or bacteria.

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