Omni-directional reflector comprising a frusto-conical surface for a|light-emitting diode.

(54) Title: OMNI-DIRECTIONAL REFLECTOR THAT INCLUDES A FRUSTOCONIC SURFACE FOR A LIGHT Emitting DIODE.

(54) Tltle: OMNI-DIRECTIONAL REFLECTOR COMPRISING A FRUSTO-CONICAL SURFACE FOR A | LIGHT-EMITTING DIODE.

(57) Summary

An optical element (100) for a lamp or lighting apparatus having a light emitting diode (LED) as a light source, which distributes unidirectional light emitted from the LED into an omni-directional output with controlled variation in intensity. light; a diffuser can also be used around the optical element and the LED to provide additional distribution of light rays by, for example, scattering; the optical element (100) is positioned adjacent to the LED and defines a central axis (CA) and a lateral axis (L) that is substantially orthogonal to the central axis (CA), the optical element (100) extends circumferentially around the central axis AC and comprises a convex light receiving surface (102) that is symmetrical around the central axis (CA) and that is positioned adjacent to the LED, a frusto-conical light-projecting surface (104) positioned laterally outside the convex light-receiving surface (102) and substantially symmetrical around the central axis (CA) and a curved light-reflecting surface (114) positioned laterally within the frusto-conical projecting surface of light (104) and substantially symmetrical around the central axis (CA), The curved light reflecting surface (114) is separated along the central axis (CA) from the convex light receiving surface (102).

(57) Abstract

Optical element (100), for a lamp or lighting apparatus having one light-emitting diode (LED) as a light source, that distributes unidirectional light output from the LED into an omnidirectional output with a controlled variance in light intensity. A diff user can also be used around the optical element and the LED to provide further distribution of the light rays by eg scattering. The optical element (100) is positioned adjacent to said LED and defines a central axis (CA) and a lateral axis (L) that is substantially orthogonal to the central axis (CA), said optical element (100) extending circumferentially about the central axis (CA) and comprising a convex light-receiving surface (102) that is symmetrical about the central axis (CA) and positioned adjacent to said LED, a frusto-conical light-projecting surface (104) positioned laterally outside the convex light-receiving surface (102) and substantially symmetrical about the central axis (CA) and an curved light-reflecting surface (114) positioned laterally inside the frusto-conical light- projecting surface (104) and substantially symmetrical about the central axis (CA), the curved light-reflecting surface (114) being spaced apart along the central axis (CA) from the convex light- receiving surface (102).

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Mexican Property

Industrial i

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PATENT TITLE NO. 338948

Owner (s): GE LIGHTING SOLUTIONS, LLC

Address: 1975 Noble Road, Bldg. 338, Nela Park. East Cleveland, Ohio, 44112, USA

Denomination: OMNI-DIRECTIONAL REFLECTOR THAT INCLUDES A FRUSTOCONIC SURFACE FOR A LIGHT-Emitting DIODE.

Classification: IC.8: G02B19 / 00

Inventor (s): DENGKE CAI; JEYACHANDRABOSE CHINNIAH; GLENN HOWARD KUENZLER

REQUEST

Number:

MX / a / 2015/001515

International filing date:

June 2013

PRIORITY

Country:

US

Date:

August 2012

Number:

13/566,623

Validity: Twenty years

Expiration Date: June 27, 2033

The reference patent is granted based on articles 1, 2, fraction ν, '6 ° 4Γ ^ ώοή ^ ΙΙΙ, and 59 of the Industrial Property Law.

In accordance with article 23 of the Industrial Property Law, this patent has a non-extendable term of twenty years, counted from the date of filing of the international application and will be subject to the payment of the fee to maintain the rights in force. .

Whoever subscribes to this title does so based on the provisions of articles 6 fractions III and 7 * bis 2 of the Industrial Property Law (Official Gazette of the Federation (DOF) 06/27/1991, amended on 02 / 08/1994, 10/25/1996, 12/26/1997, 05/17/1999, 01/26/2004, 06/16/2005, 01/25/2006, 05/08/2009 / 06/01 / 2010, 06/18/2010, 06/28/2010, 01/27/2012 and 04/09/2012); Articles 1, 3 fraction V, subsection a), sub subsection iii) 4 * and 12th fractions I and ill of the Regulations of the Mexican Institute of Industrial Property (DOF 12/14/1999, amended on 07/01/2002, 15 / 07/2004, 07/28/2004 and 09/07/2007); articles 1 ·, 3 ·, 4 “, 5 'fraction V subsection a), sub subsection ¡ii), 16 fractions I and III and 30 of the Organic Statute of the Mexican Institute of Industrial Property (DOF 12/27/1999, amended on 10/10/2002, 07/29/2004, 08/04/2004 and 09/13/2007); 1st. 3 ° and 5 'subsection a) and antepenultimate paragraph of the Agreement that delegates powers to the Deputy Directors General, Coordinator, Divisional Directors, Holders of Regional Offices, Divisional Deputy Directors, Departmental Coordinators and other subordinates of the Mexican Institute of Industrial Property. (DOF 12/15/1999, amended on 02/04/2000, 07/29/2004, 08/04/2004 and 09/13/2007).

Issue Date: May 5, 2016

DIVISIONAL DEPUTY DIRECTOR OF PATENT FUND EXAMINATION, AREAS

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OMNI-DIRECTIONAL REFLECTOR THAT INCLUDES A SUPERFÍfg3l feRÜS ^ TOC (WCAj _

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FOR A LIGHT EMITTING DIODE

FIELD OF THE INVENTION

The subject matter of the present description relates generally to Lighting devices and more particularly to Lighting devices that use one or more LEDs as a light source and an optical element to provide improved light distribution.

BACKGROUND OF THE INVENTION

Conventional incandescent lamps such as the common A19 size spotlight usually provide a relatively uniform light distribution. Specifically, the light intensity measured at a fixed distance but at different angles from a centerline axis through the focus is relatively constant. In addition to consumer appeal, this uniformity may be necessary for certain applications.

Compared to incandescent lamps, other types of light emitting devices are available that have certain advantages. For example, light emitting diodes (LEDs) can provide comparable light output with an incandescent lamp but with significantly improved energy efficiency. Additionally, the lifetime of an LED lamp can be substantially longer than that of an incandescent lamp.

LEDs can be configured in a lamp that includes a threaded base (sometimes referred to as an Edison base) so that it is interchangeable with conventional incandescent lamps. A diffuser can also be provided which, in addition to light scattering, can provide an LED lamp with a shape similar to that of conventional incandescent lamps. The color and intensity of light provided by LEDs can also be similar to that of Incandescent lamps.

However, certain challenges remain for the use of non-incandescent lamps. For example, LED lamps require an associated circuit board and generate significantly more heat than a comparable incandescent light output lamp. Furthermore, LEDs act close to Lambert sources and therefore by themselves do not usually provide a uniformly distributed omni-directional light output. LED devices are usually mounted flat on a circuit board such that the light output is substantially along a line perpendicular to the plane of the circuit board.

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In this way, the circuit board and heat management features contribute to different optical losses along each direction causing the unevenness of the light distribution from the LEDs. Providing more power to the LEDs can increase the amount of light output but may still not provide uniformity. However, this also increases the amount of heat generated which will degrade LED performance unless additional thermal management measures such as larger cooling features are taken. Still, the overall size of the lamp may be limited based on the intended application or the conventional shape of the lamp desired.

Accordingly, an optical element or lens could be useful to more evenly distribute light from a source that includes one or more of the LEDs, or alternatively an integrated chip LED that has multiple chips closely packed together. More particularly, an optical element that can provide illumination that has minor variations in light intensity but variable angles from the LEDs could be beneficial. A lighting apparatus or lamp incorporating such an optical element could also be useful.

BRIEF DESCRIPTION OF THE INVENTION

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The present invention provides an optical element for a lamp or lighting apparatus having at least one light emitting diode (LED) as a light source. Alternatively, the source may be an Integrated Chip LED (COB) which has closely packed multiple LED dies. The optical element is placed close to the LED and receives light rays from it. In turn, the optical element distributes substantially unidirectional (Lambert) light emitted from the LED into an omni-directional output with controlled variation in light intensity at different locations around the LED. A diffuser can also be used around the optical element and the LED to provide additional distribution of light rays by, for example, light scattering. Additional aspects and advantages of the invention will be set forth, in part, in the following description or may be apparent from the description or may be learned by practice of the invention.

In an exemplary embodiment, the present invention provides a lighting apparatus that includes at least one light emitting diode and an optical element positioned adjacent to at least one light emitting diode. The optical element defines a central axis and a lateral axis that is substantially orthogonal to the central axis. The optical element extends circumferentially around the central axis and includes a convex light receiving surface that is substantially symmetrical about the central axis and positioned adjacent to at least one light emitting diode; A frusto-conical surface will project light placed laterally outside the

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L '£ THE INDUSTRIAL PROPERTY convex light receiving surface and substantially symmetrical around the central axis; and a light-reflecting arcuate surface positioned laterally within the frusto-conical light-projecting surface and substantially symmetrical around the central axis, the separated light-reflecting arcuate surface along the central axis of the convex light-receiving surface.

In another exemplary embodiment, the present invention provides a lighting apparatus that includes at least one light emitting diode and an optical element positioned adjacent to at least one light emitting diode. The optical element defines a central axis and a lateral axis that is substantially orthogonal to the central axis. The optical element extends circumferentially around the central axis and includes a light receiving surface that is substantially symmetrical about the central axis and which is positioned adjacent to at least one light emitting diode, the light receiving surface forming an acute angle with the central axis; a light projecting surface that is substantially symmetrical around the central axis and that is separated from the light receiving surface along the central axis; a frusto-conical surface connected to the light-projecting and substantially symmetrical surface around the central axis; and a light reflecting arcuate surface positioned laterally within the frusto-conical and substantially symmetrical surface around the central axis, the light reflecting arcuate surface is spaced along the central axis of the light receiving surface.

In yet another exemplary embodiment, the present invention provides an optical element for a lighting apparatus having at least one light emitting diode. The optical element is placed adjacent to at least one light emitting diode. The optical element defines a central axis and a lateral axis that is substantially orthogonal to the central axis. The optical element extends circumferentially around the central axis. The optical element includes a light receiving surface that extends circumferentially around the central axis and is configured to be positioned close to at least one light emitting diode. A frusto-conical surface is separated from the light receiving surface along the transverse direction and extends circumferentially around the central axis and is substantially symmetrical around the central axis. A light reflecting arcuate surface is placed laterally within the frusto-conical surface and extends circumferentially around the central axis and is substantially symmetrical around the central axis. The optical element is configured such that light from at least one light emitting diode is emitted from the optical element with variation in light intensity measured at a fixed distance from the central axis AC over a range of zero to 135 degrees which is not more than + twenty percent of the average light intensity measured from zero to 135 degrees.

These and other features, aspects and advantages of the present invention will be better understood with reference to the following description and the appended claims. The figures

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Chaperones, which Incorporate hereby and rnnstitnypn partp dp psta pspprífiraríón ,. They illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE FIGURES

A broad and empowering description of the present invention, which includes the best way to carry out the same, addressed to a person usually skilled in the field are established in the specification which refers to the attached figures, in which:

Figure 1 provides a perspective view of an exemplary embodiment of an optical element of the present invention.

Figure 2 provides a perspective, cross-sectional view of an exemplary embodiment of Figure 1.

Figure 3 is a cross-sectional view of an exemplary embodiment of Figure 1 taken along line 3-3 of Figure 1.

Figure 4 is a schematic view, along one side of the central axis CA of the outer surface of the exemplary embodiment of Figure 1.

FIG. 5 is a schematic view showing the effect of the exemplary optical element of FIG. 1 on light rays from certain light sources as further described herein.

FIG. 6 is a graph showing light intensity as a function of position for the exemplary embodiment of FIG. 1, as will be further described herein.

Figure 7 is a perspective view of another exemplary embodiment of the present invention.

Figure 8 is a perspective view of another exemplary embodiment of an optical element of the present invention.

Figure 9 provides a perspective, cross-sectional view of the exemplary embodiment of Figure 8.

FIG. 10 is a cross-sectional view of the exemplary embodiment of FIG. 8 taken along line 10-10 of FIG. 10.

Figure 11 is a schematic view of the outer surface for the exemplary embodiment of Figure 8.

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Fig. 12 is a schematic view that rpprpqpnta pi pfprtn of the optical element of Fig. 8 on light rays from certain light sources as further described herein.

Figure 13 is a perspective view of the exemplary optical element and the LEDs of Figure 5 with an exemplary diffuser.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the embodiments of the invention, one or more examples of which are illustrated in the figures. Each example is provided by way of explanation of the invention, and not by way of limitation of the invention. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without thereby departing from the scope or spirit of the invention. For example, features illustrated or described as part of one modality can be used with another modality to obtain a different additional modality. Thus, the present invention is intended to encompass these modifications and variations to the extent that they are within the scope of the appended claims and their equivalents.

An exemplary embodiment of a lens or optical element 100 of the present invention is shown in FIG. 1 to FIG. 4. Optical element 100, which includes certain surfaces that will be described later, is substantially symmetrical about a central axis CA and extends along the circumferential direction C around the central axis CA. For purposes of further describing this exemplary embodiment of the invention, the optical element 100 defines a lateral direction L that extends substantially orthogonal to the central axis CA. Optical element 100 may comprise a light transmitting material such as, for example, glass, a polymer such as polycarbonate, or an acrylic or other light transmitting material.

Optical element 100 includes a convex light receiving surface 102. In a lighting apparatus such as a lamp, the convex light receiving surface 102 would be positioned adjacent to, or in close proximity to, one or more of the LEDs and would allow rays Light from one or more of the light sources moves to the optical element 100 (FIG. 5). Convex light receiving surface 102 extends circumferentially and is substantially symmetrical about the central axis CA. As indicated in Figure 4, for this exemplary embodiment, the convex light receiving surface is defined by a radius Ri of approximately 11.75 mm. Other radius values ​​R can also be used_b

Convex light receiving surface 102 is part of a cylindrical portion 110 of optical element 102. Cylindrical portion 110 includes a cylindrically shaped surface 108

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which is linear when viewed along the cross section shown in Figure 3. The length of the cylindrical portion 110 along the central axis CA can be varied to provide other additional embodiments of the present invention.

Optical element 100 also includes a trumpet-shaped portion 112 that is adjacent to cylindrical portion 110 along the direction of the central axis CA. The trumpet-shaped portion 112 includes a frustoconcca light-projecting surface 104 that is positioned laterally outside the convex light-receiving surface 102. The surface 104 extends cluncunferentially around, and is substantially symmetrical about the central axis CA of the optical element 100 . As shown in Figure 4, for this exemplary embodiment, the frusto-conical light-projecting surface 104 forms an acute angle with the central axis CA and forms an angle 0₆ with respect to the lateral direction L. In an exemplary embodiment, angle 0₆ forms an angle in the Interval of about 50 degrees to about 70 degrees from the lateral direction L. In another exemplary embodiment, angle θ₆ It is approximately 60 degrees.

The trumpet-shaped portion 112 also includes a light-reflecting arcuate surface 114 that is positioned laterally within the frustoconcca light-emitting surface 104. The surface 114 extends circumferentially around, and is substantially symmetrical about, the central axis CA of the optical element. 100. Although shown as a free-form curve, the light-reflecting arched surface 114 can also be described with reference to angles θ_χ, 0₂, 0₃, 0₄ and 0₅ of Fig. 4. Each of the angles 0, represents the angle relative to the lateral direction L of a line tangent to the surface 114 at positions 10, 20, 30, 40 and 50. Positions 10, 20, 30 , 40 and 50 lie in a plane that includes the central axis CA and the lateral direction L and that they are separated from each other at equal distances along the surface 114.

For an exemplary modality, 0i is approximately 63 degrees, 0₂ is about 38 degrees, 0₃ is about 24 degrees, 0₄ is about 19 degrees and 0₅ it is about 14 degrees. In another additional exemplary modality, 0_X is in the range of about 50 degrees to about 70 degrees, 0₂ is in the range of

<td>approximately</td><td> 30</td><td>degrees</td><td>to approximately</td><td> 50</td><td>degrees,</td><td>θ₃</td><td>this</td><td>in</td><td>the</td><td>interval</td><td>of</td>

<td>approximately</td><td> 20</td><td>degrees</td><td>to approximately</td><td> 30</td><td>degrees,</td><td>θ4</td><td>this</td><td>in</td><td>the</td><td>interval</td><td>of</td>

<td>approximately</td><td> 10</td><td>degrees</td><td>to approximately</td><td> 30</td><td>degrees and</td><td>θ₅</td><td>this</td><td>in</td><td>the</td><td>Interval</td><td>of</td>

about 10 degrees to about 30 degrees. Other shapes can be used for the light reflecting arched surface 114 as well.

As shown in Fig. 1 to Fig. 3, the optical element 100 also includes a flat light-projecting surface 106 that lies in a plane substantially perpendicular to the central axis CA and substantially parallel to the lateral axis L. The flat surface

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Light projector 106 is connected to the frustoconlca light projector surface 104 at an edge 116 that extends circumferentially around the central axis CA and is substantially symmetrical around the central axis CA. The flat light-projecting surface 106 also connects to the light-reflecting arcuate surface 114 at an edge 118 that extends circumferentially around the central axis CA, which is substantially symmetrical around the central axis CA and which is positioned laterally inward from the edge 116. Edge 118 coincides with location 50 (Figure 4).

Optical element 100 includes a conical shaped surface 122 that is configured in a substantially symmetrical manner around the central axis CA and is connected to the light reflecting arcuate surface 114 at edge 124. As shown, surface 122 opens along the central axis CA in the zero degree direction. Edge 124 is coincident with location 10.

A light reflecting arcuate surface 114 may be covered or coated with a highly reflective material different from the material used for the construction of the body 120 of the optical element 100. For example, the surface 114 may be metallized or covered with a coating, eg aluminum, silver or other reflective material. Other materials and / or techniques can also be used. Similarly, the tapered surface 122 can also be covered or coated with a highly reflective material different from the material used for the construction of the body 120.

Figure 5 depicts the simulated results obtained by placing optical element 100 closely adjacent to three light sources comprising LEDs 115, 117, and 119. Alternatively, multiple light sources can be replaced by an Integrated chip LED (BOC ) that has multiple dies. By way of example, light rays 126 passing through convex light receiving surface 102 pass through body material 120 and are reflected outward from arcing light reflecting surface 114 at different angles. Light rays 128 pass through convex light receiving surface 102 and then pass through conical surface 122 at different angles. Some light rays 130 pass through the convex light receiving surface 102 and then exit the optical element 100 through the flat light projecting surface 106.

A lighting apparatus incorporating optical element 100 and one or more of LEDs 115, 117, and 119 positioned adjacent thereto may also include a diffuser 136, as shown in FIG. 13. More particularly, diffuser 136 is it can be positioned around optical element 100 to provide additional scattering of light rays from one or more of the LEDs and optical element 100, as will be understood by those of skill in the art. The diffuser 136 can, for example, by a construction from a diffusive plastic material with low [PIíSS

MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

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Light absorption losses or as a glass bulb containing phosphor v placed around optical element 100 dpi and one or more of the LEDs. Diffuser 136 may connect, for example, with a heat sink and / or threaded base (eg, Edison type) (not shown).

Optical element 100 is configured to provide a more uniform light distribution than that available from an LED light source, which substantially provides a one-way light output. More specifically, FIG. 6 provides a simulated graph of light intensity (eg, in candles) as a vertical angle spur from the central axis CA for optical element 100. Using lamp 133 for example, the graph represents the Light Intensity at angles from zero degrees to 180 degrees from the central axis CA as shown (zero degrees and 180 degrees are coincident with the central axis CA). As shown in Figure 6, for the exemplary embodiment of optical element 100, the surfaces described above are configured such that the variation in Light Intensity measured at any distance from the central axis CA over the Range from zero to 135 degrees is not more than + twenty percent of the Average Light Intensity measured from zero to 135 degrees. In another exemplary embodiment, this variation in light intensity is not more than + ten percent of the average Light Intensity at angles measured from zero to 150 degrees.

Figure 7 provides a perspective view of another exemplary embodiment of an optical element 200 of the present invention similar to the exemplary embodiment of Figure 1 to Figure 4 in that it includes a convex light receiving surface 102, a frusto-conical surface projecting from light 204 and a light reflecting arched surface 214. However, the optical element 200 includes curved channels 232 on the light projecting surface 206 that extend in a substantially symmetrical manner around the central axis CA and that are circumferential around the central axis CA. Additionally, a circular surface 236 located on the central axis CA also includes a plurality of channels 238 that extend in a substantially symmetrical manner around the central axis CA and that are circumferential around the central axis CA. Channels 232 and 238 provide additional light scattering. Other surface features such as, for example, pads can also be used to provide additional light scattering.

Another exemplary embodiment of an optical element 300 of the present invention is shown in FIG. 8, FIG. 9, FIG. 10, and FIG. 11. FIG. 12 illustrates this exemplary embodiment along with LEDs 315, 317, and 319. The Optical element 300, which includes certain surfaces as will be described additionally, is substantially symmetrical about a central axis CA and extends along the circumferential direction C around the central axis CA. For purposes of further description of this exemplary embodiment of the invention, the optical element 300 also defines a lateral direction L that extends substantially orthogonal to the central axis CA. The

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Optical element 300 is constructed of a light transmitting material such as, for example, glass, a polycarbonate, an acrylic, or other light transmitting materials.

Optical element 300 includes a disk-shaped portion 310 and a trumpet-shaped portion 312. Disc-shaped portion 310 includes a light receiving surface 302. As shown, surface 302 is conical in shape and forms a acute angle with the central axis CA. However, the light receiving surface 302 may also be curved in a convex manner. In a lighting apparatus such as a lamp, the light receiving surface 302 may be placed adjacent to, or in close proximity to, one or more of the LEDs and may allow light rays from one or more of the light sources. move within optical element 300 (FIG. 12). The light receiving surface 302 extends circumferentially and is substantially symmetrical about the central axis CA.

The disk-shaped portion 310 includes a cylindrically shaped surface 308 that is linear when viewed along the cross section shown in Figure

10. The length of the disk-shaped portion 310 along the central axis CA can be varied to provide other additional embodiments of the present invention. A light projecting surface 338 connects to surface 308 and is separated from light receiving surface 302 along the direction of the central axis CA, as shown. For the exemplary modalities shown, light projection surface 338 has a frusto-conical shape. However, surface 328 may also be arched or convex in other embodiments of the Invention. As shown in Figure 11, for this exemplary embodiment, surface 338 forms an obtuse angle with the central axis CA and forms an acute angle to₈ with respect to the lateral direction L. In an exemplary embodiment, the angle a₈ it is about 25 degrees. In another exemplary embodiment, the angle a₈ it is in the range of about 20 degrees to about 30 degrees.

The trumpet-shaped portion 312 is adjacent to the disk-shaped portion 310 along the direction of the central axis CA. Trumpet-shaped portion 312 includes frusto-conical surface 304 that is connected to light-projecting surface 338. Surface 304 extends circumferentially around, and is substantially symmetrical about, the central axis CA of optical element 300 and is spaced along the central axis AC of the surface 338. As shown in Figure 11, for this exemplary embodiment, the frusto-conical surface 304 forms an acute angle with the central axis CA and forms an angle a₇ with respect to the lateral direction L. In an exemplary embodiment, the angle a₇ is approximately 28 degrees from the lateral direction L. In another exemplary embodiment, the angle a₇ it is in the range of about 23 degrees to about 33 degrees from the lateral direction L.

The trumpet-shaped portion 312 also includes a light-reflecting arcuate surface 314 that is positioned laterally within the frusto-conical surface 304. The

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INDUSTRIAL surface 314 extends circumferentially around, and is substantially symmetrical around, the central axis CA of optical element 300. Although shown as a pound whooping curve, Iii light reflective arcuate surface 314 can also be described with reference to angles a₂, α₃, α₄ to₅ already₆ of Figure 11. Each of these angles ai represents the angle relative to the lateral direction L of a line tangent to surface 314 at positions 10, 20, 30, 40 and 50, as shown in Figure 11. Positions 10, 20, 30, 40 and 50 lie on a plane that includes the central axis CA and a lateral direction L and are spaced apart from each other at equal distances along the surface 314.

For an exemplary modality, to₂ is about 51 degrees, at₃ is about 43 degrees, at₄ is about 33 degrees, at₅ it's about 23 degrees already₆ it is about 15 degrees. In another additional exemplary modality,₂ is in the range of about 46 degrees to about 56 degrees, or c₃ is in the range of

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<td>approximately</td><td> 38</td><td>degrees</td><td>to approximately</td><td> 48</td><td>degrees to₄</td><td>this</td><td>in</td><td>the</td><td>interval</td><td>of</td>

<td>approximately</td><td> 28</td><td>degrees</td><td>to approximately</td><td> 38</td><td>degrees to₅</td><td>this</td><td>in</td><td>the</td><td>interval</td><td>of</td>

<td>approximately</td><td> 18</td><td>degrees</td><td>to approximately</td><td> 28</td><td>degrees and</td><td>this</td><td>in</td><td>the</td><td>interval</td><td>of</td>

about 10 degrees to about 20 degrees. Other shapes can also be used for surface 114.

As shown in FIG. 10 and FIG. 11, optical element 300 also includes a pair of adjacent frustoconical surfaces 340 and 342 that are substantially symmetrical about the central axis CA and extend circumferentially around the central axis CA. The surface 340 and 342 are connected between the light reflecting arcuate surface 314 and the frusto-conical surface 304.

Optical element 300 includes a conical shaped surface 322 that is located in a substantially symmetrical manner along the central axis CA and is connected to the light reflecting arcuate surface 314 at edge 324. As shown, surface 322 is projected along the central axis CA in the zero degree direction. Edge 324 matches location 10.

The light reflective arcuate surface 314 can be covered or coated with a highly reflective material different from the material used for the construction of the body 320 of the optical element 300. For example, the surface 314 can be metallized or can be covered with a coating of, for example, aluminum, silver, or other reflective metal. Other materials and / or techniques can also be used. Similarly, the conical surface 322 may also be covered or covered with a highly reflective material different from the material used for the construction of the body 320.

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Figure 12 depicts the simulated results obtained by placing the optical element 100 closely adjacent to three light sources comprising LEDs 315, 317, and 319. By way of example, light rays 326 pass through the light receiving surface. 302, pass through body material 120, through surfaces 338 and 304, and are reflected off of the light reflecting arcuate surface 314 at different angles. Light rays 328 pass through light receiving surface 302 and then pass through conical surface 322 at different angles. Some light rays 330 pass through light receiving surface 102 and then exit optical element 300 through one or both of the pair of frustoconical surfaces 340 and 342.

A Lighting apparatus Incorporating optical element 300 and one or more of LEDs 115, 117, and 119 positioned adjacent thereto may also include a diffuser similar to diffuser 136 shown in FIG. 13 in exemplary embodiment 100. The element Optical 300 is equipped with a plurality of legs 344 that can be used to position and support element 300.

As with the previous modalities, optical element 300 is configured to provide a more even light distribution than is available from the LED light source. In a similar manner to that described above using Figure 6, the optical element 100 and the surfaces described above are configured such that the variation in light intensity measured at different angles from the central axis CA over the range zero to 135 degrees is not more than + twenty percent of the average Light Intensity measured at the fixed distance of zero to 135 degrees. In another exemplary embodiment, this variation in light intensity is no more than + ten percent of the average Light Intensity.

This written description uses examples to present the Invention, which include the best mode, and also allows any person skilled in the field to practice the Invention including the elaboration and use of any of the devices or systems and the realization of any of Built-in methods. The patentable scope of the invention is defined by the claims and may include other examples that experts in the field can think of. These other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with non-substantial differences from the literal wording of the claims.

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