Single-mode fiber

DSF (dispersion shifted fiber) Single-mode optical fiber whose zero-dispersion wavelength is shifted from the normal 1.3 I m to 1.55-1 m low-loss wavelength region. 

Fig. 3. Types of optical fiber (a) multimode stepped index, (b) multimode graded index, and (c) single-mode stepped index.

B. MacChesney, D. W. Johnson, P.. Lemaire, L. G. Cohen, and E. M. Rabinovich, "FluorosUicate Substrate Tubes to Eliminate Leaky-Mode Losses in MCVD Single-Mode Fibers with Depressed Index Cladding," paper no. WH2 in Technica/ Digest of Optica/ Fiber Communications Conference, San Diego, Ca/if, Optical Society of America, Washington, D.C., 1985. 

Single Mode. The single-mode fiber has a step-index profile (Fig. 16.6c) and a small core diameter (typically 10 im) such that only one mode can travel through it. This is now the preferred system, particularly for long-distance transmission. The normal light source for multimode fibers is the light-emitting diode (LED). But... 

LED do not have sufficient power for single mode fiber applications which, because of the smaller cross-sections, require more powerful lasers. The CVD of LED and laser materials is described in Ch. 15. 

Azuma, Y, Shibata, N, Horiguchi, T., Tateda,M., 1988, Wavelength dependence ofBrillouin-gain spectra for single-mode fibers, Electronics Letters, 24, 250 Beckers, J.M., 1993, Annu. Rev. Astron. Astrophys., 31, 13... 

Huss, G., Re5maud, F, Delage, L., 2001, An all guided three arms interferometer for stellar interferometry, Optics Com. 196, 55 Jeunhomme L., 1990, Single-mode fiber optics, Marcel Dekker Inc. 

Shang, H.-T., 1981, Chromatic dispersion measurement by white light interferometry on meter-length single-mode optical fiber, J. Opt. Soc. Am., 71, 1587... 

The experimental set-up for the FCS measurement is illustrated schematically in Figure 8.6. A CW Ar laser (LGK7872M, LASOS lasertechnik GmbH) at 488 nm was coupled to a single mode optical fiber to isolate the laser device from an experimental table on which the confocal microscope system was constructed. This excitation laser light transmitted through the optical fiber was collimated with a pair of lenses, and then was guided into a microscope objective (lOOX, NA 1.35, Olympus). 

Sharma N.K., Gupta B.D., Fabrication and characterization of pH sensor based on side polished single mode optical fiber, Opt. Comm. 2003 216 299-303. 

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