OisplaL.IS neuJs

Screens cleared A Health and Safety Executive re- port on vdus (see page 272) concludes that insufficient attention is paid to ergonomic factors in vdu design. The ten page report draws ten conclusions. Seven of these relate to environmental and ergonomic conditions and the remainder concern medical hazards.

Radiation emission from vdu screens was not considered hazardous, but photosensitive epilepsy was a possible risk. Visual fatigue could be avoided, assuming the user's adequate eye- sight, by giving attention to ergonomic details.

Clarity, stability, lighting levels and glare levels should all be given atten- tion if eye strain is to be avoided. 'Postural fatigue' and design factors also come up for discussion, and the hazards of long periods of vdu work and of repetitive work are mentioned.

Health and Safety Executive, Baynards House, 1 Chepstow Place, London W2 4TF, UK

12 x 7 characters The first of a range of display units, the Aller 1201 is a microprocessor- controlled vdu with a 300 mm screen and an IBM type keyboard. Consider- able care has been exercised in the design and styling to reduce operator fatigue claim the makers. The possi- bi l i ty of eye strain is greatly reduced by the use of a green screen phosphor, a clear 12 x 7 character matrix, and non-reflective keytops.

The keyboard has a separate cluster for entering numerical data, together with the scroll control keys. The scroll feature allows the operator to position the 24 line display window anywhere in the 450 lines held in the vdu's internal 4 000 character memory. The serial interface has switchable trans- mission rates between 75 and 9 600 baud. Split transmission rates are available as an option as is a 20 mA

A range of display tubes are among the largest and brightest that work at logic speeds claim their manufacturers, English Electric Valves. The single character flood gun seven segment or seven-by-five dot matrix displays include a ten character teletype rolling message display.

The tubes come in a range of colours - red, blue, white, green and yellow, and h ave a light ou tpu t o f about 7 000 cd m - 2. Encapsulan ts ensure a resilience that means that they can be safely operated in the open air and handled under operation.

English Electric Valve Co Ltd, Chelmsford, Essex CMI 2QU, UK

current loop interface. The full 96 character ASCII set is available and custom characters or control codes may be added by simple changes to the software.

Aller Services, High Street, Aller, Somerset, UK Displays expand faster Marked by a strong upsurge in Icd and gas discharge technology, industrial displays wil l prove to be a stable and expanding market up to 1985 accord- ing to a recent study. Shipments wil l more than double over the period, the report says, and the growth rate for displays is expected to outpace ew=n the overall industrial electronics market itself - by about 30%. The report, entitled The industrial display market in the US also predicts that

the cross-over in costs of crts and gas displays will occur in about 1985.

Principal growth markets will be in test and measurement, analytical instrumentation, process control and online process analysers. It is also expected that the structure of the market wil l change with a shift away from fickle consumer markets to the stable ones of industry. The shape of products to come will be altered by the use of microprocessors and ics, which will provide increased capa- bilities at reduced prices.

The report gives expected growth figures for individual display types, with Icds tripling their market assum- ing the solution of current technical problems. Gas displays, leds and, to a lesser extent, vacuum fluorescent

218 DISPLAYS. APRIL 1981