Abstract: The element consists of a light rays diffusing tube (1) made of plastic, with two layers and with circular cross-section and incorporating a large number of light emitting diodes (LED) (4) incorporated individually or as the diodes strip sets connected with the power supply source by means of electrical wiring (21). In its circumferential part, the wall of the light rays diffusing tube (1) is formed in shape resembling “U” letter with its convexity (10) oriented toward the centre of the light rays diffusing tube (1), forming a groove (9) along the whole element. The diodes (4) are adhesive bonded with their light emitting side (6) to the inner surface (11) of said convexity (10) and the whole groove (9) with the light emitting diodes (4) embedded therein, is filled with a layer (12) of epoxy resin. The layer (12) covers the diodes (4) and the electric wiring (21) in the part to which the light emitting diodes (4) are connected to said electric wiring.