LED Luminous Element for Illuminating a Light Box Having Homogeneous Light Distribution

• US 20120188755A1
• Filed: 09/15/2010
• Published: 07/26/2012
• Est. Priority Date: 09/16/2009
• Status: Active Grant

• Current Assignee: Tridonic Jennersdorf GMBH (Zumtobel Group AG)
• Original Assignee: Tridonic Jennersdorf GMBH (Zumtobel Group AG)
• Inventors: Maglica, Jure, Derkits, Christian
• Granted Patent: US 8,833,964 B2
• Time in Patent Office: Days
• US Class Current: 362/217.02
• CPC Class Codes: F21S 4/20 with light sources held by or within elongate supports
• CPC Class Codes: F21S 4/28 rigid, e.g. LED bars
• CPC Class Codes: F21V 13/02 Combinations of only two kinds of elements
• CPC Class Codes: F21V 15/013 the housing being an extrusion
• CPC Class Codes: F21V 3/04 characterised by materials, surface treatments or coatings
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G06F 13/16 for access to memory bus G06F13/28 takes precedence
• CPC Class Codes: G06F 13/18 based on priority control G06F13/1605 takes precedence
• CPC Class Codes: G09F 13/16 Signs formed of or incorporating reflecting elements or surfaces, e.g. warning signs having triangular or other geometrical shape
• CPC Class Codes: G09F 13/18 Edge-illuminated signs
• CPC Class Codes: G09F 13/22 electroluminescent electroluminescent light sources per se H05B33/00
• CPC Class Codes: G09F 2013/1831 using more than one light source
• CPC Class Codes: G09F 2013/1854 Light diffusing layer
• CPC Class Codes: G09F 2013/222 with LEDs

Abstract

The invention relates to an elongated luminous element (1) having a plurality of approximately point-shaped light sources (2) disposed along a line and having light diffusion means (3) deflecting at least one part of the light rays (12) sent out by the light sources (2) in a desired direction. The light diffusion means (3) are disposed lateral to the main emitting direction of the light sources. The elongated luminous element (1) is particularly suitable for installation in a light box (13) for advertising or demonstration purposes. The light box has a transparent or partially transparent front side (7) and a reflective back side (8). The elongated luminous element (1) or a plurality thereof is or are applied to at least one of the side areas (11, 14), such that the light rays (12) emitted by the light sources (2) and deflected by the light diffusing means (3) are aimed between or on the back side (8) and/or the front side (7) of the light box (13).

Claims

1. An elongate luminaire element (1) with a plurality of approximately punctiform light sources (2), in particular LEDs, arranged along a longitudinal direction, with a lens (6) which covers a plurality of or all of the light sources (2), and with planar light diffusion means (3), which extend in the longitudinal axis of the luminaire element (1) on one side or on both sides and parallel to the axis of symmetry of the light exit cone of the light sources (2).

2. The elongate luminaire element as claimed in claim 1, in which the light diffusion means (3) are configured such that they act as diffuse radiators on their rear side, i.e. the side remote from the light cone of the light sources (2).

3. The elongate luminaire element as claimed in claim 1, in which a plurality of planar light diffusion means (3), which have the same or else different heights, are arranged on one side or on both sides of the axis of symmetry of a light exit cone.

4. The elongate luminaire element as claimed in claim 1,

wherein scattered particles are provided in at least one light diffusion means (3).

5. The elongate luminaire element as claimed in claim 3, wherein the distance between the light diffusion means (3) and the mid-axis of the light exit cone or the distance between said light diffusion means (3) if they are provided on both sides, is selected in interaction with the height thereof such that the main cone of light, expressed by the FWHM, is directed past the light diffusion means (3), without any interaction therewith, and only the light outside the FWHM is scattered diffusely by the light diffusion means (3).

6. The elongate luminaire element as claimed in claim 1,

wherein the diffuse scattering of the light diffusion means (3) results in backscattering of some of the light in the opposite direction to the emission direction, but outside the light diffusion means (3).

7. The elongate luminaire element (1) as claimed in claim 1 characterized in that the light diffusion means (3) form a first wall and a second wall, which extend tangentially to the main emission direction of the light sources (2).

8. The elongate luminaire element (1) as claimed in claim 7, characterized in that the first wall and the second wall run along the longitudinal direction on two opposite sides of the punctiform light sources (2).

9. The elongate luminaire element (1) as claimed in claim 1, characterized in that the light diffusion means (3) have a structured surface.

10. The elongate luminaire element (1) as claimed in claim 1, characterized in that the light diffusion means (3) and the lens(es) (6) are formed integrally.

11. The elongate luminaire element (1) as claimed in claim 1, characterized in that the light diffusion means (3) and the lens(es) (6) are produced by means of an injection molding method.

12. The elongate luminaire element (1) as in claim 1, characterized in that the lens (6) has a full width at half maximum of the lens (6) of less than or equal to 30°

.

13. The elongate luminaire element (1) as claimed in claim 1, characterized in that the light diffusion means (3) consist of glass or a polymer.

14. The elongate luminaire element (1) as claimed in claim 1, characterized in that a second lens (9) is arranged above the light diffusion means (3).

15. The elongate luminaire element (1) as claimed in claim 1, characterized in that the light sources are fitted on a top-hat rail (5), for example consisting of aluminum, which is preferably in the form of a heat sink.

16. A light box (13), with a transparent or partially transparent front side (7), and with a reflecting rear side (8), having at least one elongate luminaire element (1) as claimed in claim 1, which is fitted peripherally on the light box (13).

17. The light box (13) as claimed in claim 16, characterized in that the partially transparent front side (7) is formed from a diffuser disc.

18. The elongate luminaire element (1) as claimed in claim 1, characterized in that the lens (6) is in the form of an approximately half-round bar.