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Conventional 3D Integral imaging suffers from limited image depth range due to the fixed distance between the display panel and the lens array, while digital Fresnel holography suffers from a narrow viewing angle due to the lack of a high resolution spatial light modulator. This paper proposes an original system which combines the advantages of these two techniques to provide an integral imaging system of a reasonable viewing angle with accommodation cues.

In a fibre-optic communication network, the wavelength-division multiplexing (WDM) technique enables an expansion of the data-carrying capacity of optical fibres. This can be achieved by transmitting different channels on a single optical fibre, with each channel modulating a different wavelength. In order to access and manipulate these channels at a node of the network, a compact holographic optical switch is designed, modelled, and constructed. The structure of such a switch consists of a series of optical components which are used to collimate the beam from the input, de-multiplex each individual wavelength into separated channels, manipulate the separated channels, and reshape the beam to the output. A spatial light modulator (SLM) is crucial in this system, offering control and flexibility at the channel manipulation stage, and providing the ability to redirect light into the desired output fibre. This is achieved by the use of a 2-D analogue phase computer generated hologram (CGH) based on liquid crystal on silicon (LCOS) technology.

Taking into account recent developments and present trends in devices and component technologies, the future development of electrically addressed liquid crystal spatial light modulators is considered. In particular, the combination of single-crystal-silicon active backplane and chiral smectic C liquid crystal technologies is shown to be promising. The ultimate limitations of such technologies for producing faster devices of higher complexity and functionality are assessed, and an advanced device, presently under development, is described.

An exact analysis of the diffusion of droplets in turbulent flow, taking account of the random nature of the flow and the range of length and time scales, is very involved and the equations derived are not necessarily solvable. For this reason spray models have usually not included liquid turbulent diffusion effects. Simpler models of turbulent diffusion of droplets are compared in this paper and equations suitable for insertion into existing spray models that require little extra computational effort are derived.

A method for the detection of knock using the sparking plug, and a system which allows the basic nature of the signal from the spark plug to be compared directly with that from an accelerometer are described. Results are presented for a range of engine speeds which highlight the problems and benefits of each sensing technique.

The service life of mild steel exhaust systems is limited mainly by corrosion. A useful life of two or three years is typical. Design changes can be made to extend this period, but because the process of corrosive attack is poorly understood, the changes are not necessarily as cost effective as possible. To address this problem, the way exhaust vapours condense and accumulate in a standard system has been studied. Dew point temperatures have been measured to be 48°C, and the time dependent accumulation of condensate in the rear muffler box has been recorded. The relationship between system temperature, condensate accumulation, and corrosion is discussed. The use of thermal insulation to reduce problems of condensate accumulation has been investigated. Experiments show that the increase in system temperature results in a substantial reducton in liquid accumulation at points prone to corrosive attack.

Local rates of corrosive attack in an exhaust system cannot be predicted with certainty and field trials are inherently slow. Design assessment in the laboratory under controlled conditions and minimizing the real time required to produce a reference level of corrosion, is highly desirable. In this paper, the development of a 24–hour–day test facility is described. The facility has four engine/exhaust rigs with control and data acquisition by a single microcomputer. The exhausts are tested coupled to an engine to simulate service conditions, following a cycle of user–specified running conditions. A theoretical model has been developed to provide an insight to the way cycle specification and average corrosion rates are related. The model has been used to optimize cycle conditions, minimizing test duration.