In fiber optics, most of the literature says that single-mode (SM) fiber allows only 1 mode of light to propagate/travel within, then how the same SM fiber allows WDM or DWDM, which
![Fiber dispersion and attenuation characteristics for single-mode fibers. | Download Scientific Diagram Fiber dispersion and attenuation characteristics for single-mode fibers. | Download Scientific Diagram](https://www.researchgate.net/publication/3244500/figure/fig7/AS:667846875049999@1536238511502/Fiber-dispersion-and-attenuation-characteristics-for-single-mode-fibers.jpg)
Fiber dispersion and attenuation characteristics for single-mode fibers. | Download Scientific Diagram
![Complete wavelength plans across attenuation of G.652 single mode fiber... | Download Scientific Diagram Complete wavelength plans across attenuation of G.652 single mode fiber... | Download Scientific Diagram](https://www.researchgate.net/publication/319012114/figure/fig2/AS:525688621813760@1502345342728/Complete-wavelength-plans-across-attenuation-of-G652-single-mode-fiber-ITUTG652.png)
Complete wavelength plans across attenuation of G.652 single mode fiber... | Download Scientific Diagram
![a) Experimental of our multi-wavelength imaging system; SMF, single... | Download Scientific Diagram a) Experimental of our multi-wavelength imaging system; SMF, single... | Download Scientific Diagram](https://www.researchgate.net/publication/349292473/figure/fig4/AS:1022266057965570@1620738629392/a-Experimental-of-our-multi-wavelength-imaging-system-SMF-single-mode-fiber-FC.png)
a) Experimental of our multi-wavelength imaging system; SMF, single... | Download Scientific Diagram
![2: Geometry of (a) Single-mode fiber (b) step-index multimode fiber and... | Download Scientific Diagram 2: Geometry of (a) Single-mode fiber (b) step-index multimode fiber and... | Download Scientific Diagram](https://www.researchgate.net/publication/343039775/figure/fig2/AS:914505303355393@1595046463266/Geometry-of-a-Single-mode-fiber-b-step-index-multimode-fiber-and-c-graded-index.png)