LIF Light Guide transforms sunlight into gentle, diffuse light and redirects daylight vertically as well as in horizontally in a nearly constant steradian.

The redirection to the ceiling is done within the profiles by means of total reflection.
The redirection towards the center of the room is effected by an integrated corrugated edge.

By the combined action of the different features LIF can compensate the varying incidence of sunlight due to diurnal and annual apparent movement of the sun and can reach a more uniform level of illumination throughout the room.

Without LIF the direct sunlight causes high contrasts and possibly direct and reflected glare at workplaces.

The light directing characteristics of LIF are demonstrated in the following diagrams for two different sun positions:

The diagrams show the intensity of the redirected radiation behind LIF for the incident radiation with an elevation of 45° and an azimuth of 0° resp. 45°. Additionally the position is marked where the incident light would hit by penetrating a double glazing without LIF. The arrows illustrate the self-correcting operation of the light guiding elements.