All Questions
23
questions
1
vote
0
answers
22
views
Understanding and researching with Spectroscopy
I am very new to physics so don't know a whole lot yet, so please correct any incorrect vocabulary you may find. Papers that are easy for beginners to understand are also very welcome!
Context:
I am ...
- 43
0
votes
0
answers
55
views
Is the Fourier Transform a reliable way to infer the physical phenomena producing an RF signal?
Consider the following thought experiments:
Scenario 1:
A person standing far away shines 3 light beams at you, each beam having a narrow spectral distribution centered around different frequencies F1,...
- 139
0
votes
1
answer
55
views
Can I recover the physical wavelengths present in a light source from a time-series measurement of its amplitude?
Consider a mixture of different wavelengths being emitted from the same point (ex: a star). This light consists of a mixture of wavelengths and intensities at each wavelength. When measuring the ...
- 139
3
votes
2
answers
949
views
Would the "FFT" of a light source be a reliable indicator of perceived color?
Paraphrasing from here:
A purely monochromatic 575nm wavelength light would be "perceived" as yellow, as would a light that has equal components in red and green (but no yellow). However, ...
- 139
1
vote
1
answer
106
views
450nm peak absorption [closed]
I am looking for an oxide compound (metal oxide, or similar preferably inorganic) which shows light peak absorption at 450 nm. I have troubles in finding the right compound, as most of the oxides have ...
- 113
1
vote
3
answers
72
views
Wavelengths of light outside our solar system
The question might have been asked before. Our Sun's rays decompose into 7 elementary colors by using a prism or spectrometry. Can the the colors (their number and wave length in the spectrum ) be ...
- 1,032
1
vote
0
answers
31
views
Limitations of Spectral Sensitivity Of Color Negative Film
I am trying to gain some understanding of film curves provided by the manufacturers of the film and I am confused about the Spectral Sensitivity curves. Take this for example (Screenshot of Kodak's ...
- 11
3
votes
3
answers
741
views
Why can’t we see atoms in an optical microscope?
I know, the answer to this question may seem obvious: The resolution/magnification of an optical microscope is limited by the minimum wavelength one uses. This is due to the diffraction limit.
However,...
- 469
1
vote
0
answers
33
views
Improve Spectrometer SNR
I am trying to perform optical emission spectroscopy but I have very low light intensity.
Without increasing the intensity, can I improve the SNR somehow? I am already close to the saturation point of ...
- 11
3
votes
2
answers
194
views
Why do metals appear as coloured in flame tests, while at room temperature they don't?
I'm not sure if this is more of a chemistry-type question, but my question focuses more on light spectroscopy than the chemical elements;
Why do some metals appear coloured in flame tests while they ...
- 53
2
votes
1
answer
151
views
How can imaging spectrometers identify minerals on earth from satellites
I've seen descriptions of satellites orbiting earth which can create maps of continents with elements represented as colors on a map, how can they do this? I understand how a heated black body emits ...
- 215
2
votes
1
answer
97
views
Can polychromatic light be produced from monochromatic light after passing through a crystal in transmission spectroscopy?
I have an optical setup where monochromatic light (573.5nm) is passed through a cuprous oxide crystal (Cu2O). This light is then passed through a monochromator, but the output light is actually ...
- 21
3
votes
1
answer
208
views
How does the cyan-magenta-yellow-key (CMYK) model work with printers?
I have just started to understand the subtractive colour model concept and have some questions in my mind about different scenarios. I know in the additive colour model colours are created by adding ...
- 133
0
votes
3
answers
102
views
Why don't appear all objects to be white?
When you shine light on an atom, it absorbs some of the wavelenghts; the rest determine its color. However, as far as I've understood, the absorbed wavelenghts exite the electrones moving them to a ...
- 41
0
votes
1
answer
105
views
Emission lines vs the color of an object
As far as I've understood, the color of an object depends on which wavelenghts from the more or less "white" sun light it reflects and absorbs.
I think that an atom can only absorb the light that has ...
- 41