The tag has no usage guidance.

learn more… | top users | synonyms

1
vote
2answers
91 views

Software for analysing SEM or TEM images

I am looking for a software to analyse SEM and TEM images of some PLD experiments because I want to characterize the samples, like calculate the concentration of nanoparticles, size, and do some ...
0
votes
2answers
514 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 ...
2
votes
1answer
31 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 ...
0
votes
1answer
10 views

Dissolving photoconductor (TiOPc) from Laser Printer drum possible?

When I was thinking of a Lab-On-a Chip Application which combines a lensless microscope and an optical tweezers I saw the ...
3
votes
0answers
45 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: ...
3
votes
0answers
14 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 ...
2
votes
0answers
82 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 ...
2
votes
0answers
37 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: $$ ...
1
vote
0answers
11 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 ...
1
vote
0answers
20 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 ...
1
vote
0answers
34 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 ...
1
vote
0answers
40 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 ...
0
votes
0answers
19 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 ...
0
votes
0answers
21 views

What's the difference between two types of diaphragms?

What's the principal difference between aperture iris diaphragm and field iris diaphragm?
0
votes
0answers
47 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 ...
0
votes
0answers
29 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 ...
0
votes
0answers
16 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 ...
0
votes
0answers
21 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 ...
0
votes
0answers
16 views

why the illumination in fluorescence microscope is cylinder shape?

I know that in fluorescence microscope, because the filament of the lamp is kind of cylinder shape, so in the Kohler Illumination setup, it has a image plane of the filament at the rear focal plan of ...