G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
G02B6/0081—Mechanical or electrical aspects of the light guide and light source in the lighting device peculiar to the adaptation to planar light guides, e.g. concerning packaging
G02B6/0086—Positioning aspects
G02B6/0091—Positioning aspects of the light source relative to the light guide