Lighting apparatus with controlled light emission

Abstract: A lighting apparatus (10) with controlled light emission comprises at least one light source (15) associated to a reflecting element (11). The reflecting element (11) consists of a number of units (12) overlapping one another, each one of the said units (12) having a reflecting bottom surface (13) and an absorbing top surface (14). The units (12) belonging to the reflecting element (11) overlap each other in such a way that no light emission from the light source (15) comes out directly upwards without encountering reflecting or absorbing parts.

Description: The subject of the present invention is a lighting apparatus with controlled light emission. As is known, the lighting apparatuses normally used for illuminating pedestrian precincts, squares, yards, or other public or private areas, are made, in the majority of cases, using a plurality of supports, which carry the light source, to which are associated diffusers having a spherical shape, or even different shapes. These known apparatuses represent a solution for the creation of lighting systems in all the cases in which it is essential to meet the requirements set down by standards and regulations in terms of semicylindrical illumination. However, the recent regulations that limit light emission upwards within restricted values no longer allow installation of the lighting elements referred to above, which, on account of their constructional characteristics, do not control light emission in the top hemisphere in any way. Accessories are currently available that are applied to the light sources and reduce the total light emission of the apparatus, at the same time increasing visual comfort. These accessories consist of one or more elements which are designed to intercept part of the luminous flux emitted by the apparatus. However, the said accessories are not in compliance with current standards and regulations as regards the ratio between the flux emitted upwards and the total flux emitted by the lighting element. A lighting apparatus with controlled light emission according to the preamble of claim 1 is disclosed in GB-A-202 009. A purpose of the present invention is therefore to provide a lighting apparatus that enables elimination of light dispersion upwards. A further purpose of the present invention is to provide a lighting apparatus that enables reduction of light pollution of the environment in a simple and inexpensive way. These and other purposes are achieved by a controlled light-emission apparatus as described in claim 1. Further characteristics of the invention are specified in the claims attached to the present application. Further purposes and advantages of the present invention will emerge clearly from the ensuing description and from the annexed drawings, which are provided purely to give an explanatory and non-limiting example, and in which: Figure 1 represents a partial view taken along an axis of symmetry of the controlled light-emission apparatus according to the present invention; and Figure 2 represents a view of a detail of the lighting apparatus of Figure 1. With particular reference to the above-mentioned figures, the controlled light-emission apparatus according to the invention is designated as a whole by the reference number 10. The lighting apparatus 10 is provided with a reflecting element, in turn designated as a whole by the reference number 11, which is made up of a number of units 12 overlapping one another. Each one of the said units 12 has a portion 19 adjacent to the light source 15 and has a concave shape with circular symmetry, with the concavity downwards ending in an edge 18. Each one of the said units 12 has a reflecting bottom surface 13, which is concave, and an absorbing top surface 14, which is convex. The said units 12 are moreover arranged in such a way that they surround the light source 15. In greater detail, the units 12, which belong to the reflecting element 11, overlap one another in such a way that no light emission from the light source 15 comes out directly upwards without encountering reflecting or absorbing parts. In fact, the distance between two units 12 that are adjacent to each other, and in particular the distance between their edges 18, designated in Figure 2 by the letter "d", is such that each ray emitted upwards by the source 15 that is not reflected by the reflecting surface 13 directly encounters an absorbing surface 14 belonging to the reflecting element 11. In brief, operation of the lighting apparatus according to the invention is as follows: the portion of light emitted by the light source 15 that hits the reflecting bottom surfaces 13 of the units 12 is sent towards the area to be illuminated, whereas the other portion of light hits the top surfaces 14, which absorb it, thus preventing it from being reflected towards undesired areas, as is illustrated more clearly in Figure 2. In particular, in Figure 2 it is possible to see a number of reflected rays 17, represented by dashed-and-dotted lines, which, after being reflected by the bottom surface 13 of the corresponding unit 12, reach the environment surrounding the lighting apparatus 10. In Figure 2, it is moreover possible to see a number of absorbed rays 16, represented by dashed lines, which reach top surface 14 of the corresponding unit 12 and are absorbed thereby. The distance "d" between the edges 18 of the units 12 must be determined in such a way that no emission from the lamp comes out directly, and in particular in such a way that no emission form the light source 15 comes out directly upwards without encountering reflecting or absorbing parts. The top, absorbing, surface 14 moreover prevents uncontrollable portions of the luminous flux (such as anomalous reflections, Lambert-type components, etc.) from being emitted outside the lighting element towards undesired areas. The characteristics, as well as the advantages, of the lighting apparatus that is the subject of the present invention emerge clearly from the foregoing description. Finally, it is clear that numerous variations may be made to the controlled light-emission lighting apparatus, which forms the subject of the present invention. Finally, in the practical implementation of the present invention, the materials, shapes and sizes of the items illustrated may be any whatsoever according to the requirements of the invention.

Claims: A lighting apparatus (10) with controlled light emission comprising at least one light source (15), which is associated to a reflecting element (11), wherein the said reflecting element (11) consists of a number of units (12) overlapping one another, each one of the said units (12) having a reflecting bottom surface (13) and an absorbing top surface (14), the said units (12) belonging to said reflecting element (11) overlap each other in such a way that no light emission from said light source (15) comes out directly upwards without encountering reflecting or absorbing parts, characterized in that the distance between two of the said units (12) belonging to said reflecting element (11) is such that each ray that is not reflected by the reflecting surface (13) encounters directly an absorbing surface (14) belonging to the said reflecting element (11). A lighting apparatus (10) as per Claim 1, characterized in that each one of said units (12) has a portion (19) adjacent to said light source (15) and has a concave shape with circular symmetry, with the concavity downwards ending in an edge (18). A lighting apparatus (10) as per Claim 2, characterized in that each one of said absorbing surfaces (14) has a black finish.

Inventors: GATTARI MASSIMO, QUERCETTI FRANCESCO, GATTARI, MASSIMO, QUERCETTI, FRANCESCO
Applicants: IGUZZINI ILLUMINAZIONE, IGUZZINI ILLUMINAZIONE S.P.A.
Application year: 2000
Main classification: F21V13
IPC codes: F21V13, F21V11