The present invention relates to the field of illumination apparatus. More particularly, the invention relates to LED illumination apparatus.

Background of the Invention

Some tubular, transparent shields for light tubes are known from the prior art, including US 4,393,323 and US 7,611,260. These prior art shields are formed with a plurality of heat dissipating apertures.

The present invention relates to an apparatus for utilizing these heat dissipating apertures to produce an optical effect not realized heretofore in the prior art.

US 6,361,186 discloses a neon light that is simulated using light emitting diodes aligned in a linear array as a light source. An elongated, translucent diffuser of circular cross-section is mated with an elongated opaque tubular housing of constant cross-section with a lengthwise slot. The diffuser is held in longitudinally aligned abutment against the edges of the housing slot to form a chamber between the housing and the diffuser from which light may only be emitted through the diffuser. The reflection and refraction of light by the tubular diffuser produces a neon-like glow or glare along the exposed surface of the diffuser. The housing has a maximum width not greater than the diameter of the diffuser, so that the housing is hidden behind the diffuser. The diodes may be electrically connected in patterns of alternating sequential activation to give a flashing, monochromatic effect that demands the attention of the observer and may be color coded according to the patterns of alternating sequential activation to give a flashing, color changing effect to the fixture. It is an object of the present invention to provide a novel LED illumination apparatus that generates a previously unknown optical effect.

Other objects and advantages of the invention will become apparent as the description proceeds.

Summary of the Invention

The present invention provides an LED illumination apparatus, comprising a hollow and perforated shield in which a plurality of apertures are formed throughout the periphery and length thereof; a plurality of linear arrays of LED elements housed within said shield and arranged such that light generated by said LED elements is emitted through said apertures to produce a plurality of longitudinally and peripherally spaced colored spots; and a diffusing element attached to, or in juxtaposition with, the inner surface of, and of a similar cross section as, said shield to ensure that all of said plurality of spots are illuminated at a substantially uniform light intensity.

Each of the linear arrays is mounted on a surface spaced from the diffusing element. The diffused light is therefore able to be directed through an aperture to form a distinct spot that is spaced from an adjacent spot.

In one aspect, each of the linear arrays is mounted on a block positioned in a shield interior by a plurality of spacers, each of said spacers extending between a surface of said block and a corresponding surface of the diffusing element. The block may be made of diffusing material and each of the linear arrays may be mounted on an inner face of the block. The block may have a similar configuration as the shield. Each of the spacers may be a rod or wire.

In one aspect, one or more stationary rectangular boards made of translucent or transparent material on which is mounted each of the linear arrays is housed within the shield and extend between two longitudinal ends of the shield, the one or more boards being integral with, or in abutting relation with, the diffusing element. Each of the one or more boards is fitted between opposite portions of the diffusing element.

In one aspect, first and second boards are mutually perpendicular to define four board sections, each of said board sections having two opposed mounting surfaces to each of which a corresponding linear array of LED elements is affixable.

In one aspect, the plurality of linear arrays is embodied by a single flexible conductive strip carrying a plurality of LED elements, said strip when bent being affixable to a plurality of the mounting surfaces.

In one aspect, the plurality of apertures are formed by an arrangement of peripherally spaced rows, all apertures of each of said rows being longitudinally aligned.

In one aspect, the plurality of apertures are formed by an offset arrangement whereby first and second longitudinally extending rows are alternately formed such that all apertures of a first row are longitudinally spaced from an aperture of an adjacent second row.

In one aspect,the apparatus further comprises a power supply and controller for the LED elements, and a remote control unit for transmitting radio frequency signals to said controller to thereby define operation of the LED elements. The controller is operable to control the intensity of the light emitted by each of the LED elements, to activate or deactivate the LED elements, or to control the rate at which the color of the light emitted by each of the LED elements changes. In one aspect, the shield and diffusing element are tubular and concentric. Each LED element is preferably positioned at a substantially uniform distance from a corresponding aperture through which the light propagates.

In one aspect, the ratio of aperture diameter to shield diameter ranges from 0.002 to 0.05.

When the plurality of apertures are formed by an arrangement of circumferentially spaced rows, all apertures of each of said rows are longitudinally aligned such that the ratio of spacing between adjacent apertures on a common row to shield diameter ranges from 0.2 to 0.7.

When the plurality of apertures are formed by an offset arrangement whereby first and second longitudinally extending rows are alternately formed such that all apertures of a first row are longitudinally spaced from an aperture of an adjacent second row, the ratio of spacing between apertures of adjacent rows to shield diameter ranges from 0.1 to 0.5.

In one aspect, the shield and diffusing element are of a rectangular cross section, e.g. a square cross section.

In one aspect, the shield and diffusing element have a pyramidal configuration.

Brief Description of the Drawings

In the drawings:

-Fig. 1 is a perspective view from the top of dismounted illumination apparatus, according to one embodiment of the present invention;

-Fig. 2 is an enlargement of Detail A of Fig. 1, showing an arrangement of apertures formed in the tubular shield; -Fig. 3 is a cutaway view of the perforated shield of Fig. 2, showing a plurality of LED elements housed therewithin;

-Fig. 4 is an end view B of an uncovered shield of Fig. 3;

-Fig. 5 is a cross sectional view of the illumination apparatus, cut about plane C-C of Fig. 4;

-Fig. 6 is similar to Fig. 5, with the addition of an end cap;

-Figs. 7 and 8 illustrate two implementations, respectively, of an illumination apparatus of the present invention employing the shield of Fig. 2;

-Fig. 9 is a perspective view of a shield having a rectangular cross section;

-Fig. 10 is a perspective view of a shield having a pyramidal configuration; and -Fig. 11 an end view of an uncovered shield of Fig. 9.

Detailed Description of Preferred Embodiments

The illumination apparatus of the present invention generates a unique optical effect whereby a plurality of longitudinally and peripherally spaced colored spots are illuminated at a substantially uniform light intensity throughout a hollow shield. The illumination apparatus may be used for indicating a border of a construction element while minimizing lighting costs or for decorative purposes.

Figs. 1 and 2 illustrate illumination apparatus indicated generally by numeral 10, according to one embodiment of the present invention. The light source of the illumination apparatus is constituted by a plurality of linear arrays of light emitting diodes (LEDs).

Illumination apparatus 10 comprises a tubular perforated opaque shield 5 for the LED arrays, e.g. a metallic shield, a controller 12 and power supply 15 for the LEDs, and a cable 11 extending from controller 12 to shield 5. A remote control unit 20 may be used to transmit radio frequency signals S to controller 12, for defining operation of the LEDs, for example to control the intensity of the emitted light, to activate or deactivate the LEDs, or to control the rate at which colors change, if light switching LED's are employed. Light generated by the LEDs is emitted through the plurality of apertures 7 formed throughout the periphery and length of tubular shield 5.

In order to generate the distinct spots, each LED element is positioned within the interior of shield 5 and spaced from an aperture 7 through which the light propagates. With respect to a tubular shield, each LED element may be positioned at a substantially uniform distance from a corresponding aperture 7. The width of the beam of light generated by each LED element is greater than the diameter of each aperture 7. Apertures 7 may be formed by an offset arrangement whereby first and second longitudinally extending rows 8, 9 are alternately formed within the periphery of shield 5 such that an aperture of a first row is longitudinally spaced from an adjacent second row. Thus the light generated by an LED element that is not emitted through an aperture is able to be emitted through an aperture of an adjacent row, contributing to the substantially uniform light intensity of the spots. Each colored spot that is displayed generally appears to have a diameter greater than the aperture through which the light propagates. The spacing between adjacent spots is dependent upon the spacing between adjacent apertures 7 of shield 5. For a shield diameter of 4.8 cm, the diameter of apertures 7 ranges from 1-10 mm, the spacing between adjacent apertures on the same row ranges from 1-3 cm, and the spacing between apertures of adjacent rows ranges from 0.6-2 cm.

Fig. 3 illustrates a cutaway view of shield 5. Cable 11 crossing first longitudinal edge 31 of shield 5 is connected to linear conductive strip 34 which carries a plurality of equally spaced LED elements 36. Strip 34 is adhesively affixed, or affixed by any other suitable means well known to those skilled in the art, to board 39 longitudinally extending substantially throughout shield 5, from first edge 31 to second edge 32. Strip 34 is centrally positioned on board 39 so that some of the light emitted from each LED element 36 will be transmitted through the margin of the board which is between strip 34 and terminal board edge 41 being adjacent to the periphery of shield 5.

Fig. 4 illustrates an end view of shield 5. Attached to, or in juxtaposition with, the inner surface of shield 5 and concentric therewith is a tubular diffusing element 46 for uniformly diffusing the light emitted from each LED element 36. Diffusing element 46 may be made of a polymer, e.g. Perspex, which is sandblasted or otherwise formed with non-uniform irregularities to form a frosted or any other translucent diffusing surface, or alternatively, may be made of glass, e.g. chemically etched glass.

Fitted between diametrically opposite portions of element 46 is stationary rectangular board 39, which longitudinally extends between the two longitudinal edges of shield 5. Perpendicular to board 39 and radially extending therefrom in opposite directions to element 46 are additional stationary rectangular boards 47 and 48, respectively, defining a crossed formation. Additional boards 47 and 48 are made of the same material as, are of the substantially same thickness as, and are fused to, board 39, dividing the latter into separate board sections 39a and 39b. Thus four board sections 39a, 39b, 47 and 48 are fitted within the interior of shield 5 so as to be in abutting relation with tubular diffusing element 46.

In addition to functioning as a mounting surface for a conductive strip portion, the four board sections 39a, 39b, 47 and 48 serve to divide the interior of shield 5 into four identical chambers 57. Each chamber 57 is defined by two board sections and a circumferential portion of diffusing element 46 extending therebetween. Within a chamber 57 light emitted by a plurality of LED elements 36 is uniformly diffused by tubular element 46 and then propagates through each of the corresponding apertures formed in the portion of shield 5 spanning the two board sections. The four board sections 39a, 39b, 47 and 48 may be made of a transparent material, or alternatively, may be diffusive, formed similarly as element 46 to further diffuse light refracted inwardly by element 46.

It will be appreciated that any other even number of board sections may be employed, for example eight, such that the four additional sections extend at an angle of 45 degrees from the four sections 39a, 39b, 47 and 48, to define a corresponding number of light scattering chambers.

Each board section, for example section 39a, has two opposed mounting surfaces 51a and 51b, to each of which a corresponding linear conductive strip portion carrying a plurality of LED elements is affixable.

A single flexible conductive strip may be employed, which when bent is affixable to a plurality of mounting surfaces. For example, a strip portion connected to cable 11 (Fig. 3) is affixed to mounting surface 51a of board section 39a, extending from first longitudinal edge 31 to second longitudinal edge 32. This strip portion is bent in the vicinity of second edge 32, as indicated by bent portions 44, to define a linear strip portion 56 that is affixed to mounting surface 51b of board section 48. Strip portion 56 extends to the vicinity of first longitudinal edge 31 and is then bent around board section 39b, to define a strip portion that is affixed to mounting surface 51b of board section 39b. Similarly, bent portion 54 defines a strip portion that is affixed to mounting surface 51a of board section 47 and terminates at first longitudinal edge 31. In this arrangement, four linear strips are provided. It will be appreciated, however, that any other desired arrangement of linear strips may be provided. Alternatively, a plurality of linear strips are connected to cable 11, and each of which is connected to a different mounting surface without having to form bent portions.

As shown in Fig. 5, tubular element 46 is preferably longitudinally recessed from each longitudinal edge of shield 5, e.g. the illustrated edge 32, to allow the peripheral wall of a cap to be inserted within the annular interspace 53 between shield 5 and board 39.

Fig. 6 shows a cap 58 that is inserted within the interspace between shield 5 and board 39. Cap 58 has an annular wall 59 for positioning purposes which is recessed radially inwardly from the radial outward edge 62 of cap 58. Accordingly, cap 58 is able to cover longitudinal edge 32 of shield 5 and to ensure that the generated LED light will be emitted only radially through apertures 7 and not longitudinally across the ends of shield 5.

Although not shown, cap 58 may also be perforated, in order to generate additional spaced colored spots that are perpendicular to the spots generated by the light propagating through shield 5.

The illumination apparatus of the present invention can be mounted in many different ways. The perforated shield housing the linear arrays of LEDs can be vertically mounted to serve as a pole 71, as shown in Fig. 7, or horizontally mounted to serve as a banister 73 or a railing 74, as shown in Fig. 8, for example, to provide a dazzling effect of different colors, particularly during the nighttime.

The circumferentially spaced spots provide a visual indication of the diameter of the border element while the length of the shield shows the extremities thereof. The spacing between adjacent spots indicates that the shield is a tangible object able to be grasped and not merely illuminations means. By being able to control the light intensity of the generated spots, the borders of a closet, for example, may be displayed within a darkened room to avoid accidents, yet the light intensity may be sufficiently low so as not to disturb one's sleep.

In other embodiments of the invention, the illumination apparatus may assume other configurations, including rectangular and pyramidal configurations.

Fig. 9 illustrates an illumination apparatus 80 wherein the hollow and perforated shield 82 has a rectangular cross section.

Fig. 10 illustrates illumination apparatus 90 wherein the hollow and perforated shield 92 has a pyramidal configuration.

Fig. 11 illustrates an end view of shield 82. Attached to the entire inner surface of shield 82, or in juxtaposition therewith, is a rectilinear diffusing element 86 for uniformly diffusing the light emitted from each LED element 36. A plurality of LED elements 36 are mounted on the inner face of each surface 85 of rectilinear block 84 facing a corresponding surface 87 of diffusing element 86. Block 84 is positioned in a central region of the interior 89 of shield 82 by a plurality of spacers 82, each of which extending between a surface 85 and a corresponding surface 87.

Solid block 84 is preferably made of a diffusing material in order to provide two means for diffusing the light emitted from the LED elements 36, in order to ensure even transmission of the emitted light to the apertures, thereby producing the longitudinally and peripherally spaced colored spots at a substantially uniform light intensity throughout shield 82 . The light emitted by the LED elements 36 is first transmitted through block 84 and diffused. The diffused light emitted by block 84 is further diffused by diffusing element 86 attached to, or in juxtaposition with, the inner surface of shield 82.

Each spacer 82 may be a thin rod or wire which is longitudinally spaced at a fixed or different interval from an adjacent spacer, to increase light transmission. Alternatively, each spacer 82 may longitudinally extend throughout the length of shield 82.

It will be appreciated that any other embodiment of an illumination apparatus described herein may be configured with this block and spacer arrangement.

While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried out with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without exceeding the scope of the claims.