Bool reviews

H a n d b o o k of h u m a n fac tors

G S a l v e n d y (Ed.) Wiley, N e w York (1987) £82.55 p p x x i v + 1874

This is a ve ry large compendium of reviews of the human factors (I-IF) state-of-the-art. It has over 1800 pages and 68 chapters, a r ranged in 12 sections. As with any multi-author text (103 authors), there are variations in the effec- tiveness with which the various chapter topics are handled, and there is some overlap be tween chapters - - the editor might have provided more introduction and some interspersed commentary to explore the inter-relationships be tween the various areas. As it is, the individual authors appear to have written in isolation (indeed, a few adapt material from previous publications), and there is little cross-referencing be tween chapters.

The first section, 'The HF func- tion', gives a general introduction whilst the section 'I-IF fundamen- tals' covers basic psychology, physiology and anatomy; this sec- tion is not ve ry successful at mak- ing the connections with real-life practical problems faced by designers and other potential users, though Kyllonen and Alluisi ( 'Learning and forgetting facts and skills') do produce a useful list of practical applications. Miller and Swain ('Human e r ro r and human reliability') make the connection with probabilistic risk analysis, but do not give enough space to the practicalities of improving human reliability.

The section 'Functional analysis' reviews techniques for investigat- ing systems - mainly of interest to the HF specialists. 'Job and organi- sation design' considers the design of systems and work situations for human needs, and organizational aspects; Davis and Wacker ('Job design') and Hendrick ('Organisational design') give useful reviews of those areas.

Section 5, 'Equipment and work- place design', covering displays and controls, is probably of most direct interest to readers of the Displays (but see also Sections 11 and 12). Helander gives too brief a review of 'Design of visual dis- plays': there is useful, if rather brief, coverage of legibility, loca- tion, coding, illumination factors, and a good presentation of choice of type of display. Too much space is devoted to screen reflections, visual defects, and the basics of colour perception; too little to formatting and layout of alpha- numeric and graphics VDU screens. The section contains also chapters on auditory and tactile displays, and on control design (some useful summaries by B-11inger), and Cbaffin's effective account, with some detail, of 'Biomechanical aspects of work- place design'.

'Environmental design' in Section 6 covers the physical environment, and has useful chapters on 'Noise' (Jones and Broadbent), and on 'Illumination' (Cushman and Crist). 'Design for health and safety' is concerned with injuries, physical and psycho- logical stresses: there is a detailed chapter on 'Manual materials handling' (Ayoub, Selan and Jiang), and a good account of basic shift work issues in 'Work schedules ' (Tepas and Monk), though not much on length of work periods. 'Design of selection and training systems' in Section 8 includes computer-based systems, simulators and job aids. 'Performance modelling' (of humans, primarily in decision making tasks), has Edwards' ('Decision making') clear exposi- tion of multi-attribute decision analysis, and a selective review of 'Supervisory control' by Sheridan. There are also introductory

accounts of artificial intelligence and of exper t systems. 'System evaluation' covers testing and simulating systems, and questions of maintainability, the last dis- appointing for hopes of practical guidance.

Section 11, 'I-IF in the design and use of computing systems' covers workstations, display and control aspects, programming, text edit- ing and documentation. 'Design of VDT workstations' (Grandjean) emphasizes the physical charac- teristics of workspace and screen, and omits coding and formatting of displays; there is substantial overlap with the Helander chapter in Section 5. 'Software interface design' (Williges, Williges and Elkerton) emphasizes formal design methods, and has no real guidelines in a practical sense. Effective practically oriented chapters are presented by Green- stein and Arnaut ('Human factors aspects of manual computer input devices'), Simpson et al. ( 'Speech controls and displays') and Roberts ('Text editors').

The final section is entitled 'Selected apphcations of HF in computer systems', including office automation, CAD, CAM, nuclear power control, and air traffic control. Each chapter gives some useful insights into the HF issues involved, but the coverage tends to be rather superficial in most cases. It seems a pity that these last two 'applications' sec- tions are restricted to computer- based systems; while this certainly is a prime arena for HF activities, there is much to repor t in other areas, such as public and personal transport applications, production and inspection systems, and examples of basic and service industries.

Overall, the Handbook of human factors is a welcome broad survey

DISPLAYS, OCTOBER 1988 207

Book reviews

of current HF. It will be a useful source of re fe rence both for the HF spec~,~ll,t and for the potential user of I-IF analys/s and guidance. My reconunendation is not unqua- lifted, but at least some of my critical comments must emanate from the attempt to meet such a

broad readership, and others are inevitable products of spreading such a wide range of topics over such a wide range of authors. For each individual reader , there are bound to be disappointments. A final legitimate I-IF criticism i on biomechanics: with a thickness of

70 nun, and a weight of 21. kg., it is not the easiest of texts to manipulate for reading. May we assume that further editions wi l l appear in two or more volumes?

David Whitfield

Liquid crystal tv displays: principles and applications of liquid crystal displays

E Kaneko KTK Scientific, USA (1987) £84.00 p p 308

This is an exceptionally good pub- 1/cation and it is r ecommended to all workers involved with liquid crystal displays (LCDs). The author is primarily concerned with active matrix addressed dis- plays and provides detailed descriptions of the construction, operation and electronic address- ing of the various forms of this technology. This information accounts for approxmlately half of the content of this book; the other half provides excellent descrip- tions of other types of LCDs. In particular, the author has pro- vided detailed explanations of the various drive schemes and cir- cuitry used to address complex LCDs.

The first chapter is ve ry brief and is des igned to 'set the scene' for the reader . Chapter 2 provides a very good introduction to the chemistry and physics of LCDs, describing both practical and theoretical aspects of LCDs. The third chapter, under the common theme of colour in LCDs, des- cribes the operation of electrically controlled birefr ingence LCDs, of twisted nematic displays using coloured polarisers, and of single polariser and phase change guest host displays. The use of RGB colour filters and pi-cells to pro- vide colour displays are also briefly mentioned. This is some- what disappointing given the current importance of these two technologies.

The author then provides a highly detailed description of directly multiplexed twisted nematic displays, dealing com- prehensively with a single, double and quad matrices. While this chapter is dominated by the various aspects of electronic addressing, practically useful des- criptions of the equations indicat- ing the limits of multiplexibility of the twisted nematic display and of the various techniques available for connecting the display to the drive electronics are also given. The fifth chapter descr ibes the operation of two frequency, smec- tic A, bistable phase change, ferroelectric and supertwist LCDs. Again, it was disappointing that the last two technologies were not descr ibed in the detail justified by their importance today.

The next two chapters descr ibe the whole range of approaches to the active matrix addressing of LCDs. Chapter 6 is concerned with double threshold devices and covers single diode, double diode, diode rings, metal- insulator-metal and varistor tech- nologies. In each case the current- voltage characteristics, construc- tion and the addressing wave- forms are discussed, together with some description of the relevant theory. The following chapter is devoted to the use of transistor driven matrices. In addition to a general introduction to the tech- nology, detailed descriptions of

the use of the following thin-film semiconductors are provided: cadmium selenide, tellurium, amorphous silicon, and poly- silicon. The use of single-crystal silicon transistors is also described.

The final chapter descr ibes the various approaches to the pro- duction of a large image by the use of LCDs in projection systems. Although it is brief, this chapter provides many pieces of useful information. Unfortunately a number of minor er rors appea red to have escaped the proof reader . The references at the end of each chapter are divided into topics and listed in chronological order . This arrangement is very useful, but it is disappointing to note that the latest reference given was 1985. Nevertheless, in spite of these drawbacks, the author has provided both an excellent intro- duction to and a reference book for the whole area of LCDs, which is strongly recommended to any- one involved with any aspect of LCD technology.

A MosIey GEC I-Iirst Research Centre

UE

208 DISPLAYS, OCTOBER 1988