noun
PhysicsThe amount of luminous flux per unit area.
‘Quantitative statistical information is also provided in the form of minimum, average, and maximum work-plane illuminance.’- ‘The table overleaf gives average illuminances and minimum measured illuminances for different types of work.’
- ‘The vertical illuminances on the small targets were measured for each session and are shown in Figure II - 7.’
- ‘It is one of the main advantages of task lighting that this wide range of illuminances is possible, and is immediately controlled by the person requiring the illuminance.’
- ‘The preferred horizontal task illuminances supplied by the task-lighting luminaires varied from person to person, with an average of around 600 lux.’
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