Area: OpticsOptical element with Braggs
phase grating that consists of electro-optical material or is embedded in an additional layer. The Braggs
phase grating is designed as a series of periodically applied elevations and indentations of the
waveguide's surface, coated with one layer of the compensating material and one layer of the electrically isolating material, along the propagation of light. The
phase grating is equipped with a means of generating a spatially inhomogeneous, aperiodic, external electrical field.Area of the InventionThe invention belongs to the physical area of
optics and, in fact, to the
optics methods and facilities for
spectral filtering of
optical radiation. This is based on electro-optical crystals and is to be used to produce narrow-band filters with a broad wave spectrum of
changeover to
wavelength, and for production of selective optical attenuators and modulators of light and optical equalisers.Description of the InventionThe object of the invention is, on the one hand, the production of optical elements in an integral optical design that have a multifunctional use (tuneable optical filters, selective optical attenuators and modulators, optical switches and optical equalisers), and which possess a high spectral selectivity, a broad
wavelength band of tuneability, great dynamics, and a low tendency toward cross-talk. A further aim of this invention was to develop a process for control of the aforementioned filters that makes it possible to electrically control the profile of the
transfer function, the location of the
transfer function's maximum, the number of channels to be selected, and compensation of
phase distortion, while using a relatively low control
voltage, and with a high tuneability and switching speed.The task in hand is resolved by a large number of inventions that are related by one joint intention.