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2answers
661 views

Magnification in compound microscope

I was studying about compound microscope here I don't see why we multiply linear magnification of objective with angular magnification of eyepiece. Shouldn't it be both angular or both linear? Can ...
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1answer
22 views

How can I simulate two fluorophores with a reticle?

Fluorophores typically emit in an incoherent fashion. I thought I could simulate two fluorophores (e.g. single molecule fluors) with a reticle. My concept was to make two small holes in a chrome ...
2
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1answer
33 views

CARS microscopy

I have probably very naive question. In case of CARS microscopy http://en.wikipedia.org/wiki/Coherent_anti-Stokes_Raman_spectroscopy we have $ω_{pr}+ω_{p}-ω_{S}$, how can we have minus $ω_S$? In ...
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1answer
42 views

How to perform a rotation of field of view using only mirrors/lenses?

How does one rotate a "microscope" fluorescence image on the detector using only lenses and mirrors in the set-up shown above? I am trying to do ray tracing to understand how to do this, but lenses ...
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1answer
20 views

Polarized light microscopy

Why is polarized light used in microscopy for the analysis of rocks(for example)? Why not use unpolarized light? What is it with polarized light that makes the analysis of rocks better? Edit: please ...
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0answers
37 views

Selecting an epi-illuminated objective for optical microscopy

I am currently trying to improve my silicon microphotography. To provide context: this is what I get with a 10x epi plan objective¹: This is what I get with 40x epi plan objectve with NA=0.65: I ...
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0answers
60 views

Beating the Diffraction Limit with NSOM

I am trying to understand exactly why we can beat the diffraction limit when using near-field scanning optical microscopy (NSOM). For those who aren't familiar with NSOM, check out this article: ...
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0answers
15 views

Resolution Limit for Energy Transition Imaging

I understand that when imaging the resolution limit can be given by Ewald's sphere which is due to the maximum amount of momentum that can be transferred. But how can we come up with a resolution ...
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0answers
142 views

Why do spatial filters use microscope objectives, and not other types of lenses?

A spatial filter is a device to 'clean up' a laser beam with an irregular intensity profile, and create a smooth Gaussian profile at the output. It is usually said (e.g. here) that you need a ...
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0answers
70 views

What criterion did Abbe use?

For a microscope (correct me if I am wrong) the Rayleigh Criterion gives us: $$ R=\frac{1.22 \lambda}{NA_{condenser}+NA_{objective}}$$ But with the Abbe diffraction limit: $$ ...
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0answers
19 views

influence of soft iron in magnetic lenses

I'm currently working as an intern in a research group which is specialized in transmission electron microscopes. I'm reading a book from David B. Williams and C. Barry Carter : Transmission electron ...
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0answers
55 views

Why isn't the magnifying power in a compound microscope zero when image is formed at infinity?

I think, in a compound microscope, angular magnification and lateral(or linear) magnification is given by the same formula for both image at infinity and near point(D) And the formula is ...
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0answers
13 views

Could a Kelvin Probe Force Microscope, in principal, be used as a voltmeter?

This question goes into the very nature of the work function that the Kelvin Probe Force Microscope (KPFM) measures. https://en.wikipedia.org/wiki/Kelvin_probe_force_microscope Let's say, you have a ...
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0answers
22 views

Spherical Aberration Of Electron Lenses

I would like to know why electron lenses can't have negative spherical aberration. Every textbook I have found devotes one or two sentences to saying that Otto Scherzer prooved this 80 years ago, but ...
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0answers
58 views

Importance of thickness of SiO2-substrate for observing graphene's monolayer

I've discovered that one should use 300-nm-thick SiO2 substrate in order to effectively observe graphene's monolayer through optical microscope. If thickness differs even by 5%, i.e. 315 nm, then ...
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0answers
48 views

Microscopy: aperture matching and Huygen's principle

I have repeatedly read that the maximum spatial resolution of a microscope occurs when the aperture of the objective and condenser are the same. However, I don't understand why. The resolution is ...
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0answers
22 views

What are the figures of merit/ performance measurements I can use for deconvolution?

I'm currently performing deconvolution on a bunch of 2D slices of fluorescent beads using MATLAB. Now I want to measure the performance of different deconvolution methods on the filtering of the ...
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0answers
21 views

How does one go about measuring the Point Spread Function pertaining to a particular microscope?

I am aware of the two ways in which to obtain the PSF: Theoretically and Empirically. I understand that empirically, you would have to use fluorescent beads. However, I am missing information as to ...
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0answers
22 views

Btter using a cheap RGB or Monochrome-LCD as a mask for an incoherent white light source compared to?

To be precise, I'm trying to implement ans adaptive condenser-aperture in a brightfield microscope. It's remote and I don't want to have it mechanical moving all the time when changing the objective ...
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0answers
29 views

Why the Kondo effect is important for STM?

The Kondo effect is observed when approaching 0K. Why would this effect be important for STM?
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0answers
32 views

Interaction with the Specimen in Electron Microscope

I read that Electron microscopes throws a high speed electron beam (in vacuum) on the specimen to create a magnified image of the specimen. I wish to know about the interaction of the electrons of the ...
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0answers
38 views

What's the difference between two types of diaphragms?

What's the principal difference between aperture iris diaphragm and field iris diaphragm?
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0answers
49 views

Why don't electron microscopes use huge detectors?

Electron microscopes have limited resolution. I have read experts saying that we need better electron detectors to get better resolution. Why can't we just use bigger detectors? Increase the ...
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0answers
34 views

Magnification: Microscopes Telescopes

What is the difference between the way a microscope magnifies say a star and a telescope say a cell? Why is it, that the eyepiece of a telescope magnifies stronger when it is smaller and with a ...
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0answers
17 views

A question about elastically scattering

In an electron diffraction pattern, the elastically scattered electrons are distributed over distances in the pattern corresponding to resolutions considerably higher than 1 Å. My question is can it ...
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0answers
24 views

A problem about Fresnel fringes of electron microscopy

My question is simple: Why do the Fresnel fringes at the edge of a hole in a reticulated carbon film become larger and more widely spaced when the defocus is increased? This occurs whether you are ...