Final answer:
In multimode fiber, attenuation is greater at 850 nm compared to 1300 nm due to higher scattering losses and absorption for shorter wavelengths. Shorter wavelengths are absorbed more readily and have less penetration depth, leading to increased attenuation at 850 nm.
Step-by-step explanation:
In multimode fiber optics, attenuation is a critical factor determining the fidelity and efficiency of data transmission. Attenuation refers to the reduction in power of the light signal as it travels through the fiber. The properties of light single that in a multimode fiber, the attenuation is greater at 850 nm than at 1300 nm. This difference is due to the fact that shorter wavelengths, like 850 nm, are more susceptible to scattering losses and absorption within the fiber material. Additionally, the dispersion is also greater at shorter wavelengths, further contributing to the attenuation.
Photons with a shorter wavelength, such as those around 850 nm, are absorbed closer to the surface in some materials, effectively reducing their penetration depth. This absorption effect can increase the attenuation of the optical signal at these wavelengths compared to longer wavelengths like 1300 nm, which tend to penetrate deeper and are less absorbed within the fiber core material.