- #1
The Head
- 144
- 2
I have been working with equations throughout the semester and using them to find cutoff frequencies and such, but when you say something like TE10, TE20, TE21, etc., I am realizing that I am having trouble getting a physical idea of what exactly these things are. Of course if you transmit at a frequency below the cutoff frequency of TE21, it will not propagate, but maybe TE10 modes can.
But this is what confuses me. Let's say you are transmitting at a frequency greater than the TE21 cutoff frequency. That means you can have TE10 & TE21, among other possibilities. It seems to be in this case that both of these modes are transmitting a beam of light with the same wavelength. If that is correct, then what exactly is different about these modes? The QM I remember makes me want to say that one is in an excited state, but I wouldn't know what that really means, even if true. So what different properties would two waves (of the same wavelength, if that is true) from different modes have exactly?
Finally, I am struggling to see how this applies to multimode fibers too. I heard that you can separate different modes at the end of a fiber with a grating, which makes sense if the wavelengths are indeed different. So if different modes = different wavelengths, well I am not exactly sure how these different modes run in different wavelengths anyhow...
Thanks for any of these concepts you might be able to elucidate.
But this is what confuses me. Let's say you are transmitting at a frequency greater than the TE21 cutoff frequency. That means you can have TE10 & TE21, among other possibilities. It seems to be in this case that both of these modes are transmitting a beam of light with the same wavelength. If that is correct, then what exactly is different about these modes? The QM I remember makes me want to say that one is in an excited state, but I wouldn't know what that really means, even if true. So what different properties would two waves (of the same wavelength, if that is true) from different modes have exactly?
Finally, I am struggling to see how this applies to multimode fibers too. I heard that you can separate different modes at the end of a fiber with a grating, which makes sense if the wavelengths are indeed different. So if different modes = different wavelengths, well I am not exactly sure how these different modes run in different wavelengths anyhow...
Thanks for any of these concepts you might be able to elucidate.