Robert V. VanDewoestine

Recent developments in hermetically coated optical fiber

Recent progress on the development of hermetically coated optical fiber is presented. This fiber provides improved fatigue resistance; high usable strength; and excellent resistance to hydrogen permeation, 25-90 degrees C water, and corrosive chemicals such as hydrofluoric acid and boiling sodium hydroxide. These attributes make the hermetically coated fiber an excellent candidate for use in undersea cables and other special applications where a harsh environment prevails. >

Developments in optical waveguide fabrication by the outside vapor deposition process

Improvements in optical fiber fabrication made over the last two years using the outside vapor deposition (OVD) process are reported. Advances have been made in the areas of optical and mechanical performance for existing products, dopant changes, and single-mode fiber designs. A multimode fiber having no P 2 O 5 in the core has been demonstrated which also exhibits uniform forward and cutback bandwidth-length dependence and improved resistance to the effects of hydrogen. Data is also presented on a dispersion-shifted single-mode fiber made using the segmented core approach which has recently been put into production.

Recent Results on Fatigue and Dispersion Modification in Optical Fibers

This paper reports recent results on two areas of optical fiber technology that, while unrelated, are of current interest. The first topic addresses dispersion limitation of transmission rates in optical fibers. This topic has increased in visibility in the last two years as optical amplification has minimized the importance of attenuation limits in the design of long transmission distance systems. Methods to minimize the dispersion limitation, such as dispersion shifted fiber, distributed amplification and dispersion compensating fiber, will be discussed. The second topic, that of the mechanical fatigue in optical fibers, has been a topic of research for many years, but new data continues to be gathered that is useful for cable design and system reliability calculations. Data is presented for two static fatigue tests of 3 years and 15 years duration.