Lens having mutually different optical segments

Abstract

A lighting apparatus comprising a single point-like light source, preferably a LED, and a transmissive lens structure optically connected to said light source defining a plurality of optically functional, mutually different segments dedicated for controlling the light, e.g. distribution and direction, originally emitted by said single light source. A corresponding transmissive element is presented.

Claims

1. A lighting apparatus comprising a single point light source and a flat transmissive lens structure for the single point light source having two opposing flat surfaces and being optically connected to said single point light source, wherein the lens structure comprises a plurality of optically functional, mutually different circular segments or circular sectors wherein each segment or sector is continuously arranged on the lens forming an asymmetric concentric structure having discrete areas and the lens is configured to produce an asymmetric light distribution from said single light source.

2. The apparatus of claim 1, wherein the mutually different circular segments or circular sectors are different in terms of at least one factor selected from the group consisting of: shape, size, volume, coating, amount, density, placement, and alignment of optically functional structural features.

3. The apparatus of claim 1, wherein at least one of the optically functional, mutually different circular segments or circular sectors comprises at least one optically functional feature selected from the group consisting of: surface relief form, surface relief pattern, surface relief grating, diffractive grating, diffractive profile, relief groove, relief protrusion, slanted relief profile, blazed relief profile, symmetric relief profile, asymmetric relief profile, refractive profile, and a number of refractive Fresnel profiles.

4. The apparatus of claim 1, wherein at least one of the optically functional, mutually different circular segments or circular sectors is configured for establishing at least one optical function selected from the group consisting of: light directivity management, diffusion, collimation, diffraction, coloring, scattering, and distribution control.

5. The apparatus of claim 1, wherein at least one of the optically functional, mutually different circular segments or circular sectors comprises a curved functional surface feature.

6. A luminaire unit comprising a plurality of apparatuses of claim 1.

7. An optically transmissive element for at least optically connecting to a single point light source to form a lighting apparatus therewith, wherein said optically transmissive element consists of a plurality of optically functional, mutually different continuously arranged circular segments or circular sectors forming an asymmetric concentric structure having discrete areas and being configured for jointly controlling the light distributed and directed from said single point light source, wherein the optically transmissive element includes a flat transmissive lens structure for the single point light source having two opposing flat surfaces and the lens is configured to produce an asymmetric light distribution from the single point light source.

8. The apparatus of claim 1, wherein the single point light source is a light emitting diode (LED).

9. The apparatus of claim 5, wherein the curved functional surface feature is a circular feature.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Next the invention will be described in greater detail with reference to the accompanying drawings, in which:

(2) FIG. 1 illustrates an embodiment of a lighting arrangement in accordance with prior art.

(3) FIG. 2A illustrates an embodiment of a lighting apparatus in accordance with the embodiment of the present invention.

(4) FIG. 2B depicts surface design options, related parameters and shapes for the embodiment of FIG. 2A.

(5) FIG. 3A illustrates another embodiment of a lighting apparatus in accordance with the present invention.

(6) FIG. 3B depicts surface design options, related parameters and shapes for the embodiment of FIG. 3A.

(7) FIG. 4 depicts an embodiment of a multi-LED solution with multiple light sources, each allocated with a dedicated lens structure.

DETAILED DESCRIPTION

(8) The suggested optically transmissive element, e.g. a lens, may generally be substantially planar, e.g. of a planar/low-height cylindrical shape. Further, it may be curved or contain curved shapes. It may define a substantially circular surface area on one or two, potentially opposing, sides thereof. At least it may have a circular cross-section. Alternatively, other shapes may be utilized, e.g. angular such as rectangular, triangular, hexagonal or generally polygonal shapes regarding the cross-section and/or the surface(s).

(9) A segment may define a discrete (functionally, structurally and/or visually distinguishable) half circle area (or have a half circle projection) on the lens surface. Alternatively, a segment may define a quarter circle or area of some other shape with e.g. (straight) line and/or curve type boundary with a neighbouring segment or the environment. A segment is adjacent to at least one other segment of the lens.

(10) The lens is designed for serving a single point-like light source such as LED, but many LED+lens combinations can be conveniently brought together to generate a larger illumination fixture preferably having common housing.

(11) FIG. 2A illustrates, via a top/plan view, an embodiment of a lighting apparatus in accordance with the embodiment of the present invention. Especially the transmissive element (lens) 202 is shown in the figure. Light source itself, typically only a single LED, is now shown in the figure as it does not, as such, form the inventive core of this embodiment, but e.g. the sketch 106 of FIG. 1 incorporating LED 108 is applicable also here what comes the coarse positioning of the light source relative to the lens 202, i.e. the lens is at least optically connected to the LED so that the light emitted therefrom is incident on the lens 202, propagates through the lens 202 and is finally emitted or outcoupled therefrom with desired properties regarding e.g. distribution, direction, collimation, diffusion, etc. The lens 202 is thus configured for controlling the light (e.g. distribution and direction) originally emitted by the single light source.

(12) At this point, it is generally noteworthy to mention that the lens structures in accordance with embodiments of the present invention may optionally contain functional coating(s) and/or film(s), the function of which may be optical, protective, anti-scratch, moisture repelling (hydrophobic), etc.

(13) Reverting to FIG. 2A, the embodiment comprises three segments 204, 206, 208 for light management. In this example, each segment generally or roughly defines a half circle area, each area having a different period and profile of grating grooves thereon. The surface (relief) patterns of the segments 204, 206, 208 may be considered to form an overall or aggregate surface pattern of the whole lens surface.

(14) Within the area of the segment the period and pattern/profile of the relief forms remain unchanged. For instance, the provided grooves may be few microns, e.g. about 9 m deep, and may rotate around the origin thus following the general form of the segment. Diameter of the overall component may be about 70 mm.

(15) FIG. 2B depicts surface design options, related parameters and shapes for the areas 1, 2 and 3 of the respective segments 204, 206, 208 of the embodiment of FIG. 2A. Groove periods range from about 8 microns to about 20 microns. Gratings within the areas are continuous.

(16) Area 1 of segment 204 starts from the origin (e.g. centre of lens surface) whereas areas 2 and 3 of segments 206, and 208 do not as they begin further away therefrom. The lens 202 may have an empty area 210 free of optically functional features between the segments 208 and 206, 204.

(17) Alternatively, the numeral 210 may refer to a dent, cavity or even a through-hole in the lens structure 202.

(18) FIG. 3A illustrates, via a top/plan view, another embodiment of a lighting apparatus in accordance with the present invention. Transmissive element (lens) 302 is shown in the figure.

(19) The embodiment comprises three segments 304, 306, 308 for light management. The surface (relief) patterns of the segments 304, 306, 308 may be considered to form an overall or aggregate surface pattern on the lens surface. Generally the grooves may be similar to the ones of FIG. 2A.

(20) FIG. 3B depicts surface design options, related parameters and shapes for the areas 1, 2 and 3 of the respective segments 304, 306, 308 the embodiment of FIG. 3A. Groove periods range from about 29 microns to about 67 microns. Gratings within the areas are continuous.

(21) Area 1 of segment 304 starts from the origin (centre of lens surface) whereas areas 2 and 3 of segments 306, and 308 do not as they begin further away therefrom. The lens 302 may have an empty area 310 free of optically functional features between the segments 208 and 206, 204. Alternatively, the numeral 210 may refer to a dent, cavity or even a through-hole in the lens structure 202.

(22) FIG. 4 depicts an embodiment of a multi-LED solution 402 with multiple lighting apparatuses described hereinbefore, potentially integrated within common housing, each apparatus comprising a dedicated light source allocated with a dedicated lens structure 404, 406, 408. The lenses may, as a whole, establish a lens matrix.