Transparency optical power limiters

Multifunctional materials will play an important role in the development of Photonics Technology. This paper describes novel multifunctional polymeric composites for applications in both active and passive photonic components. On the molecular level, we have introduced multifunctionality by design and synthesis of chromophores which by themselves exhibit more than one functionality. At the bulk level, we have introduced the concept of a multiphasic nanostructured composites where phase separation is controlled in the nanometer range to produce optically transparent bulk in which each domain produces a specific photonic function. Results are presented from the studies of up-converted two-photon lasing, two-photon confocal microscopy, optical power limiting, photorefractivity and optical channel waveguides to illustrate the application of the multifunctional optical composites. 

Current discussions of potential applications of nonlinear optical signal processing in computers (7), both general and special purpose, and in communications for functions such as switching, amplifying, and multiplexing are primarily focussed on devices for the manipulation of laser beams in thin transparent films. With particular reference to bistable optical devices, the fundamental physical mechanisms which provide limits on speed, power dissipation, and size of optical switching elements have been discussed (8). 

After the studies on transparency, a complete high-speed optical network based on POFs became realistic. However, despite these advances, the SI POF had a limitation in bandwidth, requiring the excitation of several tens of thousands of modes for transmission. The large core increases modal dispersion and drastically degrades the bandwidth to approximately several hundred megahertz over 100 m. The concept of fiber bandwidth originates from the general theory of time-invariant linear systems [42]. If the optical fiber can be treated as a linear system, its input and output powers in the time domain are described simply as follows ... 

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