Light can alter the appearance of a room or area without physically changing it. Light directs our view, influences perception and draws our attention to specific details. lighting process can be used to divide and interpret rooms in order to emphasise areas or establish continuity between the interior and exterior. Light distribution and illuminance have a decisive influence on how architecture is perceived.

Light can be used to emphasise individual functional zones in an area, e.g. traffic areas, waiting areas, and exhibition areas. Zonal lighting with delineated beams of light visually separates one area from another. Different illuminance levels establish a perceptual hierarchy and direct the viewer’s gaze. The differentiation of light colors creates contrasts and emphasizes individual zones.

Differentiated lighting process of functional zones divide up an area and improve orientation. Areas of a space can be separated from each other using narrow beams of light and strong contrasts in brightness. Distinct contrasts between individual zones and their surroundings remove them from their spatial context. Large areas that on the whole are evenly illuminated can appear rather monotone if they are not divided up. Low general lighting provides the basis for adding lighting accents. Lighting control systems allow functional zones to be adapted to different uses.

Floor illumination emphasises objects and pedestrian surfaces. Vertical spatial borders are emphasised by illuminating wall surfaces. Uniform light distribution emphasises the wall as a whole, whereas accentuating, grazing light gives the wall structure by adding patterns of light. Bright walls create a high level of diffuse light in the room.

Vertical illumination is used to shape the visual environment. Room surfaces can be differentiated using different levels of illuminance to indicate their importance. Uniform illumination of the surfaces emphasizes them as an architectural feature. A decreasing level of brightness across a wall is not as effective as uniform wallwashing at defining room surfaces. Lighting effects using grazing light emphasise the surface textures and become the dominant feature. Indirect lighting of a ceiling creates diffuse light in the room with the lighting effect being influenced by the reflectance and colour of its surface.