All Questions
Tagged with signal-processing visible-light
6
questions
1
vote
2
answers
530
views
Why does a photomultiplier tube (PMT) traditionally present better signal-to-noise ratio (SNR) than an avalanche photodiode (APD)?
Empirically, a photomultiplier tube (PMT) is said to present better signal-to-noise ratio (SNR) than an avalanche photodiode (APD). Some materials say that it is attributed to the higher gain and ...
- 11
0
votes
0
answers
77
views
Dispersion of light
I've been taking digital signal processing course. It's pretty interesting for me. One thought came to my mind while I've been practicing numerical problem on Fourier transform.
So my question is ...
- 121
0
votes
2
answers
129
views
Why doesn't central obscuration put a big dot in the middle of a PSF for a centrally obscured optic?
I'm confused as to how central obscuration effects the PSF. Low pass filters make sense since they are inherently oriented with dealing with spatial frequency, resulting in blur in the spatial domain....
- 119
4
votes
1
answer
206
views
Thin Film Interference, thinning each layer one by one
I have three layers of different complex refraction index.
I am shining with a laser of wavelength lambda onto the layers.
Through etching, each layer is etched one by one, and hence one by one, the ...
- 111
6
votes
5
answers
2k
views
Existence of monochromatic pulses?
Why there can not be a monochromatic pulse? My physics professor told us that we can't generate a monochromatic light pulse and I was wondering what are the physical limitations causing this.
- 69
9
votes
2
answers
873
views
How would one generate Brownian light? What would it look like?
When light is an equal mix of all visible frequencies, we call it white light.
By analogy, sound that is a mix of all audible frequencies is called white noise.
For sound, there is an additional ...
- 22.1k