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Sir Gareth Roberts made a stunning impact on the UK science scene, and his influence and reports brought optimism back into the university sector at a time when morale was low. He will be most remembered for his term as Chairman of the Committee of Vice-Chancellors and Principals (CVCP) in 1995, when the UK government announced savage cuts in university funding, and the CVCP responded by a threat to impose a levy on all first-year students. This led to the 1997 Dearing inquiry into higher education, which recommended many of the points made by Roberts, including fees on a loan basis, access for disadvantaged groups, and support for the vital role of university teaching. The Labour government accepted most of the recommendations, and large increases in university funding followed. In 2001 Roberts was asked to review the problem of the growing shortage of people with science, technology, engineering and mathematics skills, and his report, SET for success , was specifically commended by the Prime Minister. Additional funds were provided to raise the stipend of research students, to bring forward measures to recruit and retain science and engineering teachers, to modernize school and university science laboratories, and to create a new national centre for science teaching. He was primarily responsible, as Chairman of the Research Careers Initiative, for implementation of the Concordat, which set out clearly for the first time the need for a career structure for research students, and the way forward to achieve this. His prominence in the national scene might easily cause his earlier scientific achievements to be overlooked, although they were most significant. He first concentrated on the physics governing the injection of electrons into insulators and wide-gap semiconductors, and the laws governing their transit. This led to an interest in organic semiconductors, and his was the first publication on an efficient low-voltage organic light-emitting diode (LED). Concerned that evaporation harmed the properties of organic thin films, he improved the design of the Langmuir–Blodgett trough and developed their technique into a reliable method for the preparation and study of organics. He used the trough for research on a variety of materials, and many groups around the world followed his leadership, gaining much knowledge on the optical and electronic properties of organic conductors and insulators.

This paper describes the history and science behind the development of modern flat-panel displays, and assesses future trends. Electronic displays are an important feature of modern life. For many years the cathode ray tube, an engineering marvel, was universal, but its shape was cumbersome and its operating voltage too high. The need for a flat-panel display, working at a low voltage, became imperative, and much research has been applied to this need. Any versatile flat-panel display will exploit an electro-optical effect, a transparent conductor and an addressing system to deliver data locally. The first need is to convert an electrical signal into a visible change. Two methods are available, the first giving emission of light, the second modulating ambient illumination. The most useful light-emitting media are semiconductors, historically exploiting III–V or II–VI compounds, but more recently organic or polymer semiconductors. Another possible effect uses gas plasma discharges. The modulating, or subtractive, effects that have been studied include liquid crystals, electrophoresis, electrowetting and electrochromism. A transparent conductor makes it possible to apply a voltage to an extended area while observing the results. The design is a compromise, since the free electrons that carry current also absorb light. The first materials used were metals, but some semiconductors, when heavily doped, give a better balance, with high transmission for a low resistance. Delivering data unambiguously to a million or so picture elements across the display area is no easy task. The preferred solution is an amorphous silicon thin-film transistor deposited at each cross-point in an X – Y matrix. Success in these endeavours has led to many applications for flat-panel displays, including television, flexible displays, electronic paper, electronic books and advertising signs.

Francis Edgar Jones was born on 16 January 1914 in Wolverhampton. His father, the son of a miner, was educated at the Rugby Grammar School and a teachers’ training college, and became a teacher in 1898. He met Frank’s mother, whose family name was Franks, while teaching at Barnet. Early in the 1900s they moved north to Wolverhampton and remained there until they moved again to Dagenham in 1921. Frank was the third born in a family of two boys and two girls. At the age of just under five he was sent to the Church of England Primary School at Heathdown, Wolverhampton, where the discipline was strict. Frank had a vivid recollection of life at the school: ‘When we arrived at a quarter to nine, we first had to place our hands on the desk in front, palms face down, to see that we had clean nails. Next we had to stand on the form to have our boots inspected to make sure they were clean. After prayers, school began and our reward for a good week’s work was to be allowed to work with raffia - of different colours - on Friday afternoons.’

A special issue of Semiconductor Science and Technology commemorating the 50th anniversary of the diode laser contained a number of excellent detailed descriptions of early laser research in the US, France and the USSR [2012 Semicond. Sci. Technol. 27 (special issue)]. To complete the picture, this paper describes some of the research then current in the UK and is intended to set the whole scene in context.

Publisher Summary This chapter discusses the use and abuse of III–V compounds. The III–V compounds were invented when excitement over the transistor was being tempered by realization of the limitations of germanium. At that time, all devices had to be made in pulled single crystals, and silicon was viewed with great suspicion, as the high growth temperature, over 1400°C, would certainly result in impure crystals. None of the III–V compounds occur naturally, and the Siemens Company and Professor Heinrich Welker were able to secure a valid worldwide patent on semiconductor devices in compounds made from the third and fifth groups of the Periodic Table. This new physics can be exploited by making new types of diodes and transistors, optically bistable layers, highly photosensitive diodes, and quantum-well lasers whose emission wavelength depends on the dimensions, as well as the material.

Liquid crystal displays (LCDs) are commonly found in portable equipment. The main criticisms aimed at these displays are their asymmetric angle-of-view and dull grey appearance, which is particularly acute in low ambient lighting. However, by the inclusion of a fluorescent dye, it is possible to fabricate partially-emissive LCDs with a virtually hemispherical angle-of-view. This effect has been demonstrated succesfully for a range of dyes based on the perylene diester chromophor. An energy transfer mechanism between the liquid crystal host and dye molecule has been identified. This effect was used to enhance the fluorescence intensity.

The fourth European Solid State Device Research Conference will be held in Nottingham on 16-19 September 1974. An exhibition associated with this conference will be held in the Department of Applied Science, University of Nottingham. It will be open between 10.00 and 16.30h for the duration of the conference to conference delegates and ticket holders. Tickets are available from The Exhibition Department, The Institute of Physics, 47 Belgrave Square, London SW1X8QX. Details of the exhibits are given in this feature.

The transmission of the atmosphere for radiation of wave-lengths between 1 and 14 μ has been determined at sea-level, and its dependence on meteorological conditions investigated. Measurements have been made over paths of 2264 and 4478 yd., and the correlation with visibility and humidity studied in detail at four chosen wave-lengths, 2.18, 3.61, 10.01 and 11.48 μ ,. Spectral transmission curves for typical conditions have been recorded for the complete range 1 to 14 μ and, in addition to the numerous absorption bands due to water vapour arid carbon dioxide, some bands caused by the rarer constituents, in particular N 2 O and HDO, have been observed. Throughout the wave-length range investigated, the transmission varies with the visibility, the effect being less marked at the longer wave-lengths. For example, when, under typical conditions, the visual transmission falls from 75 to 50% per sea mile, the corresponding change at 2.18 μ is from 85 to 73%, and at 10.01 μ from 87 to 83%. At the latter wave-length there is a strong dependence on the quantity of water vapour in the path. Assuming that the observed variations of infra-red transmission with visibility are due to the scattering of radiation by salt nuclei the characteristics of a suitable size distribution have been calculated. As the humidity increases the nuclei absorb moisture and increase in size. The distribution is in agreement with the limited observations on size and concentration that have been reported. For a visual transmission of 40% per sea mile the radius of the most frequently occurring droplet is calculated to be 0.4 μ .

The standard thin-film transistor configuration, used in TFT-matrix addressing of complex liquid crystal displays, has an inherent design fault in that there is a metal-metal crossover associated with each transistor. This arrangement makes shorts and open circuits more likely with increase in panel size. In this paper, a modification is proposed that overcomes this problem.

Money spent on defence seems to arouse more passion than almost any other budget item. Defence research is probably the most emotive subject of all, and many scientists are reluctant to support attempts to protect them from potential aggression.

DR. CYRIL HILSUM, the only chief scientific officer of the Ministry of Defence appointed to a research position, found himself just after the Second World War working for the Admiralty rather than staying on at University College, London, as its Physics Department's first post-war postgraduate research student. He was sent to join Admiralty headquarters, and after working on the British infrared programme, moved on to compound semiconductors. He was one of the scientists involved in investigating gallium arsenide's instabilities, although it was Gunn who named the oscillation effect and the resulting diode. He now researches with The Royal Signals & Radar Establishment on solid-state flat-panel displays, and holds the highest scientific-officer grade the UK Civil Service can offer without administrative responsibilities. CAROLINE WEINSTEIN went to see him recently to talk about a little of his career and his views on science and technological research in the UK.

Liquid crystal displays (LCDs) are commonly found in portable equipment. The main criticisms aimed at these displays are their asymmetric angle of view and dull grey appearance, which is particularly acute in low ambient lighting. It has been demonstrated that by the inclusion of a fluorescent dye it is possible to fabricate emissive LCDs with virtually a hemispherical angle of view.