The resolution R (here abstinent as a distance, not to be abashed with the angular resolution of a antecedent subsection) depends on the angular breach α:
R=\frac{1.22\lambda}{\mathrm{NA}_\text{condenser} + \mathrm{NA}_\text{objective}} area NA = ηsin θ.4
Here NA is the after aperture, θ is bisected the included bend α of the lens, which depends on the bore of the lens and its focal length, η is the refractive basis of the average amid the lens and the specimen, and λ is the amicableness of ablaze anecdotic or appearing from (in the case of fluorescence microscopy) the sample.
It follows that the NAs of both the cold and the condenser should be as top as accessible for best resolution. In the case that both NAs are the same, the blueprint may be bargain to:
R=\frac{0.61\lambda}{\mathrm{NA}}\approx\frac{\lambda}{2\mathrm{NA}}
The applied absolute for θ is about 70°. In an air cold or condenser, this gives a best NA of 0.95. In a high-resolution oil captivation lens, the best NA is about 1.45, if application captivation oil with a refractive basis of 1.52. Due to these limitations, the resolution absolute of a ablaze microscope application arresting ablaze is about 200 nm. Given that the beeline amicableness of arresting ablaze is violet (λ ≈ 400 nm),
R=\frac{1.22 \times 400\,\mbox{nm}}{1.45\ +\ 0.95} = 203\,\mbox{nm}
which is abreast 200 nm.
Oil captivation objectives can accept applied difficulties due to their bank abyss of acreage and acutely abbreviate alive distance, which calls for the use of actual attenuate (0.17mm) awning slips, or, in an astern microscope, attenuate glass-bottomed Petri dishes.
However, resolution beneath this abstract absolute can be accomplished application a diffraction address alleged 4Pi STED microscopy. By berserk absorption two beams on a point source, altar as baby as 30 nm accept been resolved.5
R=\frac{1.22\lambda}{\mathrm{NA}_\text{condenser} + \mathrm{NA}_\text{objective}} area NA = ηsin θ.4
Here NA is the after aperture, θ is bisected the included bend α of the lens, which depends on the bore of the lens and its focal length, η is the refractive basis of the average amid the lens and the specimen, and λ is the amicableness of ablaze anecdotic or appearing from (in the case of fluorescence microscopy) the sample.
It follows that the NAs of both the cold and the condenser should be as top as accessible for best resolution. In the case that both NAs are the same, the blueprint may be bargain to:
R=\frac{0.61\lambda}{\mathrm{NA}}\approx\frac{\lambda}{2\mathrm{NA}}
The applied absolute for θ is about 70°. In an air cold or condenser, this gives a best NA of 0.95. In a high-resolution oil captivation lens, the best NA is about 1.45, if application captivation oil with a refractive basis of 1.52. Due to these limitations, the resolution absolute of a ablaze microscope application arresting ablaze is about 200 nm. Given that the beeline amicableness of arresting ablaze is violet (λ ≈ 400 nm),
R=\frac{1.22 \times 400\,\mbox{nm}}{1.45\ +\ 0.95} = 203\,\mbox{nm}
which is abreast 200 nm.
Oil captivation objectives can accept applied difficulties due to their bank abyss of acreage and acutely abbreviate alive distance, which calls for the use of actual attenuate (0.17mm) awning slips, or, in an astern microscope, attenuate glass-bottomed Petri dishes.
However, resolution beneath this abstract absolute can be accomplished application a diffraction address alleged 4Pi STED microscopy. By berserk absorption two beams on a point source, altar as baby as 30 nm accept been resolved.5
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