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A remarkably bullish forecast of the growth prospects for Japan's optoelectronics industry was contained in a report on the industry published earlier this year by the Economics Division of the Long Term Credit Bank of Japan. The industry was seen as growing to be as important as the electronics industry, with which it was seen as forming the mainstay of Japan's future industry. Believing it would be of interest to a wider readership we publish here a shortened version of the report.

The current generation of light wave systems benefit from increased transmission distance by using optical amplification and increased capacity by using dense wavelength division multiplexing (DWDM) technology. The reach of present systems is limited by the noise contributed by the used amplifiers, combined with nonlinear effects from transmission. This paper aims to address these issues.

The nature and extent of degradations in the optical DWDM systems due to these limiting factors have been discussed in this paper.

It has been learnt that stimulated Raman scattering (SRS), four wave mixing (FWM) and amplified spontaneous emission (ASE) are the important factors in optical DWDM systems. These factors limit the system capacity of the transmission systems drastically.

It can be concluded from the discussion that while designing an efficient DWDM system, an optimization of the channel separation and the amplifier separation is required to minimize the nonlinear effects (FWM and SRS) along with the ASE noise introduced by inline optical amplifications.

Recent advancements in the domain of smart communication systems and technologies have led to the augmented developments for very large scale integrated circuit designs in electro-magnetic applications. Increasing demands for low power, compact area and superior figure of merit–oriented circuit designs are the trends of the recent research studies. Hence, to accomplish such applications intended for optical communications, the transimpedance amplifier (TIA) was designed.

In this research work, the authors present a multi-layer active feedback structure which mainly composes a transimpedance stage and a gain stage followed by a low pass filter. This structure enables to achieve improved input impedance and superior gain. A simplified cascaded amplifier has also been designed in a hierarchical topology to improvise the noise effect further. The proposed TIA has been designed using Taiwan Semiconductor Manufacturing Company 45 nm complementary metal oxide semiconductor technology. Moreover, the thermal noise has been analyzed at −3 dB bandwidth to prove the reduction in thermal noise with increase in frequency for most of the devices used in the designed circuit.

The proposed differential TIA circuit was found to obtain the transimpedance gain of 50.1 dBO without applying any external bias current which is almost 8% improvised as compared to the conventional circuit. In addition to this, bandwidth achieved was 2.15 GHz along with only 38 W of power consumption, which is reasonably 100 times improvised in comparison of conventional circuit. Hence, the proposed differential TIA is suitable for the low power optical communications applications intended to work on low supply voltage.

The designed work is done by authors in university lab premises and is not copied from anywhere. To the best of the authors’ knowledge, it is 100% original.

The purpose of this paper is to provide an overview of the research in a project aimed at developing manufacturing techniques for integrated optical and electronic interconnect printed circuit boards (OPCB) including the motivation for this research, the progress, the achievements and the interactions between the partners.

Several polymer waveguide fabrication methods were developed including direct laser write, laser ablation and inkjet printing. Polymer formulations were developed to suit the fabrication methods. Computer‐aided design (CAD) tools were developed and waveguide layout design rules were established. The CAD tools were used to lay out a complex backplane interconnect pattern to meet practical demanding specifications for use in a system demonstrator.

Novel polymer formulations for polyacrylate enable faster writing times for laser direct write fabrication. Control of the fabrication parameters enables inkjet printing of polysiloxane waveguides. Several different laser systems can be used to form waveguide structures by ablation. Establishment of waveguide layout design rules from experimental measurements and modelling enables successful first time layout of complex interconnection patterns.

The complexity and length of the waveguides in a complex backplane interconnect, beyond that achieved in this paper, is limited by the bend loss and by the propagation loss partially caused by waveguide sidewall roughness, so further research in these areas would be beneficial to give a wider range of applicability.

The paper gives an overview of advances in polymer formulation, fabrication methods and CAD tools, for manufacturing of complex hybrid‐integrated OPCBs.

Fiber nonlinearities are anticipated to impose transmission limitations due to the enhanced total interaction length in long‐haul dense wavelength division multiplexing (DWDM) optical transmission systems. The purpose of this paper is to analytically study the combined effect of stimulated Raman scattering (SRS) and four‐wave mixing (FWM) in the presence of amplified spontaneous emission (ASE) noise generated by erbium‐doped fiber amplifiers (EDFAs).

The paper presents analytical analysis of DWDM optical transmission systems in the presence of two significant fiber nonlinearities (SRS and FWM).

Simple expressions are derived to study the dependence of signal‐to‐noise ratio (SNR) on the amplifier spacing between two consecutive amplifiers.

The authors have analytically studied the combined effect of SRS and FWM in the presence of ASE noise generated by EDFAs. The novelty of the work is that it has considered all the three factors simultaneously and the expressions are derived for calculation of SNR.

Fiber optics has the capability to dramatically increase telecommunications capability and lower costs. This article examines fiber optic technology, explains some of the key terminology, and speculates about the way fiber optics will change our world.

The design of optical fibres for applications where many performance targets have to be met simultaneously is a non‐trivial process. An evolutionary strategy (ES) combined with an algorithm to model the appropriate fibre parameters was used to design an optical fibre suitable for long haul high bandwidth communications. The ES code was developed using an object oriented approach and a parallel version was also incorporated. This allowed for the rapid implementation and subsequent design of fibres with properties of interest. Design constraints arising from the fibre manufacturing process were incorporated.

Optical fibre sensors are finding wide applications in biotechnology and medicine, as a European specialist explains.

The purpose of this paper is to present a review of research performed at the Communications Research Centre Canada on sensing applications of femtosecond infrared laser‐inscribed Bragg gratings.

By using fibre Bragg gratings induced with ultrafast infrared radiation, inscription of high temperature stable sensors in standard and exotic optical waveguides is investigated for a variety of novel applications.

Generally, femtosecond laser‐induced gratings are effective sensors that can be applied in situations and environments where most fibre optic sensors are not effective.

The paper is a review of existing work already published in the literature and provides an overview of this technology to the reader.

Optoelectronic components such as lasers and avalanche photodiodes have already revolutionised long distance transmission, and yet the technology is still in its infancy. Future generations of optoelectronic components will see the increasing integration of electronic, optoelectronic and optical functions on single chips, bringing about dramatic improvements in performance and the lower costs that will be required for widescale introduction of broadband networks and services.