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Viewing conditions on worktops when writing in a hall lighted by electric lamps

Multimedia projectors are used increasingly in academic centres and ensuring good visibility of the screen requires the limiting of light in classrooms. The purpose of the paper was to evaluate the quality of artificial general lighting on worktops used for writing in a didactic room. It was measured with full lighting and for three variants (degrees) of lighting dimmed during the display of a multimedia presentation. There were 24 measuring points set in the room and the intensity of the lighting was measured with a luxmeter. After setting the potentiometer half-way between the maximum and minimum level of lighting, which switched on automatically once the projector was on, the brightness at most of the measuring points was less than the required 500 Lx. With the minimum lighting for this mode, the visual discomfort was recorded in the students’ working areas. Therefore, a conclusion was made that didactic spaces with multimedia projectors should be additionally equipped with task lighting such as lamps fixed on every worktop used for note taking. Introducing smart lighting systems which facilitate dynamic collaboration of general and local lighting would help to improve viewing conditions in the room and reduce energy consumption of electric lamps.