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“One picture says more than 1000 words”. This saving offers us information about one of the most important features of human beings. Human beings mostly relate their actions to their surroundings by optical means. No other information channel is as well developed as the optical channel and only the optical channel is able to process very large quantities of data at one time, bearing in mind the large number of steps which are between the image received by the eyes and the understanding of the contents of the picture by the brain.

The purpose of this paper is to describe optical flow‐based navigation of a very light fixed‐wing aircraft in flight between obstacles.

The optical flow information of two cameras mounted on the aircraft is used to detect the obstacle. It is assumed that the image processing has been completed and the optical flow vectors have been obtained beforehand. The optical flow is used to detect the obstacles and make a rapid turn manoeuvre for the aircraft.

It is shown that using the optical flow feedback by itself is unable to give a rapid turn to the aircraft and its rate should be employed into the control law. Six degree‐of‐freedom flight simulation showed that the proposed navigation and control strategy give satisfactory results in different flight environments like corridors with parallel and non‐parallel walls and in the L junctions. Simulations also showed that the aircraft flight velocity has little effect on collision avoidance performance.

This paper provides a theoretical framework to study the different parameters affect the obstacle detection and avoidance of an aircraft.

An analytical equation has been developed to relate the obstacle detection distance to the aircraft manoeuvrability parameters. In addition, an optical flow‐based controller also has been designed to provide rapid turn manoeuvres using the aileron control surface.

The purpose of this paper is to improve photoelectric detection target (PDT) optical detection performance and detection view, by analyzing its influence factors and putting forward a new method to design its optical detection system.

Using rectangle linked photoelectric detector, with low noise and high response, to design optical detection system and gain faint projectile image information; bringing forward a deviating focusing technique to eliminate detection blind area of photoelectric detector; and designing adjustable slit diaphragm to weaken background light influence.

The results of experimentation in shooting range show that the new PDT has improved detection sensitivity and performance.

The paper presents a new design method in photoelectric detection target (PDT) optical detection system, which can provide a new method to design fire across measurement system and gain accurate projectile's coordinates data in the shooting range.

The purpose of this paper is to introduce a method for increasing imaging quality in impedance tomography. The paper presents an optical method of shape virtualization, processing algorithm draft and results of virtualization for sample objects.

In impedance tomography the image reconstruction algorithms must yield accurate images of impedance changes. One of the keys to producing an accurate reconstructed image is the inclusion of prior information regarding the physical geometry of the object. When the object under investigation is filled with transparent medium, optical methods can provide information about its interior and estimate the shape of non‐transparent interjections. Computer graphics methods (e.g. ray tracing) can be used to simulate propagation of the light transmitted along straight lines within the object, and thus yield geometric data to better imaging. The process of setting up boundary conditions is then supplied with additional information about interior of the object, which can significantly improve solution of the forward problem in impedance tomography.

The visibility matrix includes information about the interior of the object. However, the information is incomplete since the scanning is done along one axis. In order to obtain all remaining data, scanning along three axes is required. On the basis of the visibility matrix, the shape and volume of the non‐transparent interjections are recovered and then estimated.

The biggest novelty is indeed the combination of methods used in optical tomography with those in impedance tomography.

Granted that the Information Superhighway is here, what are the nine imperative issues arising from the explosion of content? was the question we discussed in Chapter 6. Bill Gates puts the date of the Information Superskyway (as we prefer to call it) at least a decade away; and Michael Dertouzos, Director of MIT Computer Science Laboratory since 1974, deplores the decade that will be wasted. What are the Technology, Demand, and Supply Issues that drive/delay the Highway/Sky‐way? Technology Issue 1: Hardly anybody is working on Shared Conventions for interconnected machines to work together. Dertouzos warns: Major players of the 1990s who keep extolling fiber optics, real‐time video, virtual reality, multimedia, and electronic commerce will discover that none of these awesome stuff will be useful unless computers and software at diverse sites can “understand” one another. Supply Issue 1: Dertouzos' war of spiders is one in which 3C industry members each offer the customer a car to drive on the Highway so long as he(she) never drives another car or wheeled vehicle. Supply Issue 2: Dertouzos declares: “There is no true information infrastructure anywhere in the world today.” Everybody is busy putting up toll booths, but nobody is putting up the highway. Demand Issue 1: Europeans declare “Good roads create traffic.” Video on demand is too small to justify the massive investment necessary to connect just the US homes to the broadband network. Europeans urge the Economic Community to remove IT barriers. Demand Issue 2: American and European experts concur that customer and business applications are the driver. This concurrent emphasis on applications confirms the USE‐orientation: What do you USE the high‐speed, high‐capacity switched network for? which we raised as Issue 1 in Chapter 6. Demand Issue 3: In his keynote address to the Harvard Conference on Internet and Society, Intel Vice President McGeady blasted Digital Pundits (Al Gore, Nicholas Negroponte) for taking us down the wrong path of interactive television which would simply subject us to an avalanche of advertising… They all failed to realize that the information reformation is about personal information, not about the same old stuff turned into bits and delivered to your doorstep in a slightly new way. It's about creating on one's own. Technology Issue 2: Technologically, what is the promise; what is the bottleneck? Combining the advantages of two technologies ‐ optics and semiconductors ‐ holds the best promise of reliable, fast, and inexpensive storage and transfer, communication and computing.

The purpose of this paper is to present the need, and a potential solution, for in‐plane routing of optical signals for optical‐enabled circuit boards.

Multimode waveguides and integrated 45° in‐plane mirror structures were made in a low loss acrylate‐based photopolymer using excimer laser ablation. The fabrication of multimode waveguides and mirrors was carried out in a single laser system which minimised alignment issues.

It was established that in‐plane mirror fabrication using laser ablation can be achieved and can potentially be used to define mirrors in waveguides made by other methods such as photolithography.

While the concept (integrated in‐plane mirror) was demonstrated, the viability of its deployment will depend on the results of optical loss measurements for which further research is required.

The paper gives an overview of the design concept and fabrication steps for an in‐plane embedded mirror.

At the 1978 Aslib conference, I gave a talk entitled ‘The New Technology’, subsequently summarised in a short article in this journal. In it a drawing of something I called the ‘Consumersole’ appeared. This device, which was discussed in an article also published in 1978, was a prediction of what might be used in homes and businesses at the end of the century.

The purpose of this paper is to introduce a new device with eddy current microscope (ECM) to test the invisible and buried subsurface flaws in metallic specimens.

When coil is excited by intermittent impulse signal, the eddy current effect happens among the tested metal specimen which is near the coil. Because of magnetic‐optic effect caused by eddy current magnetic field, the magnetic‐optic film changes the polarization direction of the passing linear polarization beam. The beam, containing the defects' information, can be accepted by charge‐coupled device (CCD) after being reflected through beamsplitter, and the imperceptible flaws in subsurface of mental product can be visually tested.

Integrating the eddy effect fully with Faraday's magneto‐optic (MO) effect can realize the visual non‐destructive testing for the subsurface defects.

Manufacturing defected specimens and improving the resolving power of the MO image remain difficult and need further research. A better image processing system needs to be developed to ascertain the characters of the defects.

After additional experiments, this device may find practical application on the inspection of flaws under the surface of metal specimens.

The device presented in this paper can detect the small defects that are hardly seen by eyes at the surface and the subsurface of metal specimens, and have them detected by the CCD.

A simple, parallel‐mode tactile transducer for extracting three‐dimensional digital representations of complex engineering components is proposed. In addition, algorithms for computer processing of the tactile information to produce a compact structural description of the scrutinised object are evolved. The possibility exists that these techniques might be applied to future generations of robot devices with sensory feedback.