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As bit rates of optical interconnects increase, a large amount of complicated signal conditioning is needed to compensate for the insufficient bandwidth of current modulators. In this paper, we evaluate the reduced equalization requirements of high-bandwidth plasmonic modulators in short-reach transmission experiments. It is shown that transmission of 100 Gbit/s non-return-to-zero (NRZ) and 112 Gbit/s pulse-amplitude modulation-4 over 1 km and 2 km distance is possible without any receiver equalization. At higher bit-rates, such as 120 Gbit/s NRZ, data transmission is demonstrated over 500 m with reduced receiver equalization requirements. Transmission up to 200 Gbit/s over 1 km is also shown with more complex receiver equalization. The reduced complexity of the receiver digital signal processing is attributed to a flat frequency response of at least 108 GHz of the plasmonic modulators. All single wavelength transmissions have been performed at 1540 nm in standard single mode fiber.

For pt.1 see ibid., vol.45

A coherent, optical, multichannel television distribution system with 140 Mbit/s CMI-coded, optical FSK modulation, is described. The system is operated over 11 km monomode optical fibres. The transmitter modules are controlled via a polarisation-independent monitoring unit, using optical fibre technology. The superheterodyne receivers are equipped with an optical polarisation-diversity input. A sensitivity of -48.8 dBm is achieved, with an intermediate frequency linewidth of more than 80 MHz. System performance parameters are detected over a time-period of 54 hours.

An analytical method is developed for the determination of the deformation of a viscous fluid in a vacuum tube being scanned by an electron beam. Assuming a sinusoidal surface charge pattern, the resulting electrostatic boundary value problem is solved and the electrostatic forces are thereby determined. Assuming again a sinusoidal surface deformation and using the linearized Navier-Stokes differential equation, the resulting hydrodynamic boundary value problem is solved. In steady state conditions between electrostatic and hydrodynamic forces, closed-form expressions are obtained for the deformation, the dependence of which on system parameters are shown in diagrams.

The image quality achieved by light-valve projectors, e.g. their resolution limit, is mainly determined by the Schlieren-optical process, the deformation process of the control layer, and the deposition of definite charge patterns on the layer. The author gives an analysis describing those processes for the single-gun light valve. Evaluating the analysis, the application of this principle to HDTV large-screen displays appears to be limited due to several reasons which are essentially traced back to diffraction limitation and interference of the spatial carrier frequencies used for multiplexing the primary colour components. Improvements are proposed based on finer gratings on the control layer.