Accommodation and visual fatigue in display work

Abstract Being in the midst of the evolution of the species Homo termino-videns, demands for (eye) rest-time allowances are commonplace among vdu operators the world over. Today some 13 per cent of Swedish salaried employees daily sit at a vdu and Sweden is the first country to have issued national safety and health directives on vdu work. Experiments using a laser optometer have shown that visual tasks in vdu work may induce temporary effects in the visual accommodation system; increased refractive power in darkness (‘night myopia’) and levelling-out of accommodation responses in good lighting (‘distance myopia’ and ‘near hyperopia’). It is believed that laser optometry will eventually make possible the formulation of objective criteria of visual fatigue and its prevention.