LIGHT-EMITTING DIODE ILLUMINATION DEVICE Russian patent published in 2011 - IPC G02B6/00 

FIELD: physics.

SUBSTANCE: illumination device has a cover with a base and a window opposite the base of the cover for illumination of a liquid crystal display in particular; at least one light guide in form of a think plate, having two opposite main front surfaces and at least two faces (B1, B2, B3, B4), on one of the front surfaces of the light guide turned towards the base of the cover, a light-scattering optical structure for scattering light propagating in the light guide; at least one printed circuit board parallel the base of the cover on the side of the base of the cover and light-emitting diodes (Lnm) lying on a line along at least one of the faces of the light guide. Light emitted by the light-emitting diodes, which illuminate the light guide through the face, is scattered by that front surface of the light guide having a light-scattering optical structure. Light-emitting diodes lying on the line along at least one of the faces of the light guide are arranged in at least two rows (Rb1~Rb8) and in such a way that the light-emitting diode (Lnm) of one row, powered by an electric power source (S-S8), follows the light-emitting diode (L(n+1)m) of another row powered by another source.

EFFECT: minimising change in uniformity of illumination, maintaining sufficient brightness for illuminating the liquid-crystal display.

20 cl, 8 dwg