|Publication number||US5803592 A|
|Application number||US 08/755,011|
|Publication date||Sep 8, 1998|
|Filing date||Nov 22, 1996|
|Priority date||Nov 22, 1996|
|Publication number||08755011, 755011, US 5803592 A, US 5803592A, US-A-5803592, US5803592 A, US5803592A|
|Inventors||Lawrence Richard Lawson|
|Original Assignee||Austin Air Systems Limited|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (15), Referenced by (74), Classifications (24), Legal Events (4)|
|External Links: USPTO, USPTO Assignment, Espacenet|
There are many applications, such as the transillumination of dense x-ray films, the photo-reduction of transparencies, the shadlowless illumination of objects including the human face and for certain types of medical treatment lamps which must be viewed directly by the patient, where a Lambertian light source having high brightness and often large size is desirable. While diffuse reflection is commonly used in light fixtures, it is treated in design either haphazardly or aesthetically, due to its intrinsically forgiving nature with respect to angles and placements. Detailed ray tracing is seldom applied to the design of such fixtures. Light source designs based on ray tracing usually utilize specular reflection, such as shown in U.S. Pat. Nos. 1,515,221, 1,811,782, and 1,279,096 as well as high uniformity. Diffuse reflection has also been employed from time to time in the construction of laboratory surface brightness standards. These standards have often utilized integrating spheres or partial integrating spheres, to achieve extremely high uniformity. But, these designs, requiring multiple reflections off a diffuse reflective surface, have been costly and inefficient. Consequently, they have not found applications in general lighting. The light source assembly according to the invention preferably takes advantage of diffuse reflection rather than specular reflection to achieve these goals, and typically provides a unique geometric arrangement between component parts which help achieve its advantageous results.
"Uniformity" is typically measured by percentage of non-uniformity, high uniformity being a low percentage of non-uniformity. Non-uniformity is the ratio of the difference of the brightest and dimmest surface brightness areas (of the surface) divided by the average surface brightness. High uniformity is achieved when non-uniformity is about 10% or less, and non-uniformity in the 5-10% range is considered highly desirable and may be readily obtained according to the present invention. "Brightness" relates to the surface brightness (brightness of a surface) and is typically measured in footlamberts. While what "high brightness" is depends upon the particular application, a surface brightness of about 2000 footlamberts or more is considered "high brightness" for many applications, and can also readily be obtained according to the present invention.
According to one aspect of the present a light source assembly is provided comprising the following: A light emitting element. A first reflector having an interior diffuse reflective surface comprising a portion of a surface of revolution, having a center axis. A second reflector. And, a diffuser. The diffuser is connected to the first reflector, the light emitting element is substantially centrally located on the center axis, and the second reflector is located between the diffuser and the light emitting element.
The particular geometric relationship between the elements set forth above that is desirable according to the present invention is determined with respect to the radius, R, of the surface of revolution. The center of the generally rod-like light emitting element is positioned on the central axis approximately 0.1 R from the intersection of that axis with the interior surface of the first reflector. The center of second reflector is positioned on that same axis approximately 0.2 R from its intersection with the first reflector. It has a diameter approximately 0.3-R-0.4 R (e.g. about 0.35 R). Preferably, the center of the diffuser is located on the central axis within a range of ±0.3 R from the origin. With regard to the shape of the first reflector, it should be understood that its shape need not be exactly spherical, but may be ovoid or parabolic etc. to some degree without a material alteration in performance. The exact shape of the second reflector as well as its reflectance are still less consequential. For instance, were the reflectance of the second reflector made equal to zero, good uniformity could still be obtained, but efficiency would be diminished. Hence while the terms "radius" and "diameter" are used in the specification and claims, these are to be understood as being "effective radius" or "effective diameter".
In practice the first reflector preferably is a partial sphere, such as a hemisphere, or a partial ovoid, such as a hemi-ovoid. Alternatively it may be ellipsoidal or parabolic. For example, a paraboloid obtained from a 3-point parabolic fit to the central axis intersection and two opposite points on the edge of a hemispherical primary reflector could be used effectively as a primary reflector producing almost as good a result as the hemispherical reflector itself. In certain instances an ellipsoidal shape, although more difficult to manufacture, might slightly enhance performance.
The light emitting element preferably comprises an arc lamp, such as a metal halide lamp, and only a single lamp is typically necessary, although more than one lamp may be provided where desired. Alternatively a filament lamp may be used instead of an arc. But, for best results, an extended light emitting element should have a cylindrical shape.
The reflecting surface of the first reflector should provide non-directional, diffuse scattering as reflection. The first reflector interior surface may comprise a finish of the material forming the first reflector so that it is a diffuse reflective surface. For example if the first reflector is made out of metal the surface of the metal may be finished in such a way that the interior thereof provides a diffuse reflective surface. Normally the diffuse reflective surface is most easily obtained by providing a coating of diffuse reflective paint, such as integrating sphere paint. A particularly high quality integrating sphere paint is Kodak barium sulfate paint, but cheaper alternatives may be more cost effective. For example, selected kaolins mixed with modified titanium dioxide have proven effective as pigments. Where a paint is utilized, the paint may have added pigments or phosphors for color modification. Since only the diffusely scattered light exits the lamp, the source itself need not emit visible light when phosphors are used. Narrow band illumination may be obtained in this way.
The second reflector concentrates the light energy along the wall of the first reflector thereby increasing the intensity at the edge of the diffuser. It also serves to limit direct illumination of the diffuser to its outer edge if not eliminating it altogether depending on the length of the cylindrical light emitting element. The combination of these geometric effects serves to balance the center and edge intensities. When the diameter of the light emitting element is narrow and its length is short, ripples may appear in the radial intensity function as defined from the center to edge of the diffuser. These may be reduced or eliminated by feathering the edges of the second reflector. The nature of the reflectance of the second reflector is of minor importance in determining intensity distribution. The rear surface should have the highest reflectance possible in order to maximize efficiency. It may be polished although diffuse reflection is generally preferred. The reflectance of front surface of the second reflector has a small effect on the central brightness of the diffuser. Adjusting this reflectance may help fine-tune the central portion of the radial light distribution. The second reflector may be mounted directly on the light emitting element or mounted on any accessory support preferably made of fine spring-tensioned wire.
The diffuser may comprise any suitable diffuser, of a transparent or translucent material typically of hard plastic or glass. The diffuser has an interior surface with an outer periphery adjacent the first reflector. To offset the effect of non-unity index of refraction on rays reaching the outer periphery and making an oblique angle with the normal to the diffuser surface, the diffuser may be given an anti-reflection coating or selective roughening on its internal surface. To reduce heat radiation the diffuser may incorporate an infra-red reflective coating such as is used on window glass. The diffuser may be directly connected to the first reflector and supported by it, either mechanically (by interfering surfaces, or with fasteners) attached, or it may be adhesively attached. Alternatively an indirect connection may be provided.
Where the first reflector is substantially hemispherical and the light emitting element is a single metal halide lamp, the lamp and diffuser may have dimensions proportional to about 175 watts for the lamp and 19 inches in diameter for the diffuser for an R=10 inches first reflector. The surface brightness of the assembly at the diffuser may be at least about 2000 footlamberts, e.g. about 2100 footlamberts, and the non-uniformity at the diffuser is 10% or less (e.g. about 5%).
According to another aspect of the present invention a light source assembly is provided comprising the following: A light emitting element. A first reflector having an interior reflective surface comprising a portion of a surface of revolution having a radius R, and having a center axis. The light emitting element positioned on the center axis approximately 0.1 R from the first reflector interior surface. A second reflector positioned approximately 0.2 R from the first reflector interior surface along the center axis; and having a diameter, substantially perpendicular to the center axis, of approximately 0.3 R-0.4 R (e.g. about 0.35 R). And, a diffuser connected to the first reflector, the second reflector located between the diffuser and the light emitting element.
The details of the second reflector, primary reflector, and other components preferably are as described above.
According to yet another aspect of the present invention a light source assembly is provided comprising the following: A single metal halide lamp. A housing containing the lamp and including an interior and an exterior. At least about half of the housing interior having a diffuse reflective surface. A diffuser defining part of the exterior. And, when the lamp is energized the assembly at the diffuser having a surface brightness of at least about 2000 footlamberts and a non uniformity of 10% or less.
It is the primary object of the present invention to provide a Lambertian light source with high uniformity and high brightness, which can be made in a wide variety of sizes, including large sizes (e.g. of about 250 square inches or more). This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.
FIG. 1 is a side schematic view, primarily in cross-section but partly in elevation, of an exemplary light source assembly according to the present invention;
FIG. 2 is a bottom plan view of the assembly of FIG. 1 with the diffuser removed;
FIG. 3 is a schematic diagram which illustrates diffuse reflection;
FIG. 4 is a view like that of FIG. 1 for a second embodiment of a light source assembly according to the invention; and
FIG. 5 is a bottom plan view of the second reflector from the FIG. 4 embodiment.
An exemplary embodiment of a light source assembly according to the present invention is shown generally by reference numeral 10 in FIG. 1. It comprises a light emitting element 11 which is mounted in a housing, for example the housing defined by a first reflector 12. The first reflector 12 has a center axis 13, and an interior surface 14 comprising a portion of a surface of revolution.
The light emitting element 11 may comprise a wide variety of different elements. For example it may comprise an arc lamp, such as a metal halide lamp, or a filament lamp in which cases the longitudinal axis of the arc or filament is to be coincident with the center axis, 13. A single lamp may be provided in either case and is preferred, although a number of different lamps may be provided if desired. The element 11 is connected up to an electrical source 15 by any conventional means, and the element 11 may be mounted directly to the top 16 (at or adjacent the center axis 13) of the first reflector 12, for example held in place by a collar, bushing, bracket, or the like. Alternatively any other suitable means, such as accessory clamps, brackets, or supports, may be provided for mounting the element 11, as long as it is substantially centrally located on the center axis 13, as illustrated in FIG. 1.
The first reflector 12 may be made of any suitable material having the necessary rigidity and support characteristics, such as a metal, hard plastic, or the like. Regardless of the material of the reflector 12, however, the interior surface 14 is a reflective surface, and desirably a diffuse reflective surface. The diffuse reflective surface may be formed by polishing, finishing, burnishing, or otherwise treating the actual material forming the reflector 12 in some circumstances, or may be formed by providing a coating of material on the reflector 12 to form the reflective surface 14. For example a diffuse reflective paint, such as an integrating sphere paint, may be provided to define the diffuse reflective surface 14. One example of such paint is Kodak barium sulfate paint, but other less expensive alternatives may be more cost effective. Where a paint is utilized, the paint may have conventional pigments or phosphors for color correction.
The first reflector 12 surface of revolution preferably comprises a partial sphere (such as a hemisphere), a partial ovoid (such as a hemi-ovoid), or may be parabolic. As clear from a comparison of FIGS. 1 and 2 (solid line in FIG. 2) a partial sphere, substantially comprising a hemisphere, is illustrated in the drawings. However as shown by dotted line at 12' in FIG. 2 a partial ovoid configuration may alternatively be provided. Alternatively the surface of revolution of the surface 14 may be parabolic; for example a 3 point parabolic fit to the substantially hemispherical surface 14 already illustrated in FIG. 1 would not result in a great degradation in performance. Also instead of the reflector 12' being ovoid as illustrated in FIG. 2, an ovoid insert may instead be provided within the substantially hemispherical reflector 12.
The assembly 10 further comprises a second reflector 18 and a diffuser 19, the second reflector 18 being disposed between the light emitting element 11 and the diffuser 19 along the center axis 13. The second reflector reduces the apparent surface brightness of the center of the first reflector 12, and blocks the majority of direct illumination of the diffuser 19 by the light emitting element 11. In the embodiment illustrated in FIGS. 1 and 2 the second reflector 18 completely blocks direct illumination of the diffuser 19 by the light emitting element 11. The second reflector 18 may be of any suitable material such as metal, the surface facing the light emitting element 20 of which is reflective (e.g. polished, coated, or the like), and the second reflector 18 may be mounted within the assembly 10 by any suitable mechanism. For example as illustrated in FIG. 1 it may be mounted directly on the bottom end 21 of a casing for the light emitting element 11. Alternatively it may be mounted by one or more brackets, clamps, cables, wires, or the like directly to the primary reflector 12 or to some exterior structure.
The diffuser 19 is preferably substantially planar and may comprise any conventional diffuser. Transparent or translucent glass or hard plastic is preferred. The diffuser 19 is connected to the primary reflector 12 either directly or indirectly. For example as illustrated in FIG. 1 the external peripheral lip 23 may actually make surface engagement with the internal periphery of the reflector 12 adjacent the bottom 24 thereof, or it may be held in place by mechanical fasteners such as screws or clamps, or by adhesive. Alternatively the diffuser 19 may be indirectly connected to the reflector 12 by a collar, brackets, or other suitable conventional structures.
In the FIGS. 1 and 2 embodiment the various components are provided with particular geometric relationships. The interior surface 14 surface of revolution has a radius R with the light emitting element 11 positioned on the center axis 13 approximately 0.1 R from the first reflector 12 interior surface 14 at the top 16, and the second reflector 18 surface 20 positioned approximately 0.2 R from the first reflector 12 interior surface 14 along the center axis 13. The second reflector 18 has a diameter, substantially perpendicular to the center axis 13, of approximately 0.3 R-0.4 R (e.g. about 0.35 R) (as seen in both FIGS. 1 and 2). The diffuser 19 is located in a range of ±0.3 R from the intersection 26 of imaginary radii of the first reflector 12 interior surface 14 along the light emitting element (that is the center axis 13) and perpendicular to the light emitting element (shown in dotted in at 27 in FIG. 1). The diffuser 19 typically is circular in plan and has a diameter D, the diameter D equal to 2 R when the surface 14 is an exact hemisphere (that is the diffuser 19 is along the radii 27).
While the values that R and D may take may vary widely, as well as the intensity of the light emitting element 11, for the exemplary structure illustrated in FIGS. 1 and 2 one desirable set of values is for R to equal ten inches, D to equal nineteen inches, element 11 to comprise a single 175 watt metal halide lamp, the surface 14 to be a partial sphere coated with barium sulfate paint, and the second reflector 18 to be circular in plan (as illustrated in solid line in FIG. 2). In such a situation the surface brightness of the diffuser 19 is at least about 2000 footlamberts, typically about 2100 footlamberts, and the assembly 10 has a non-uniformity, at the diffuser 19, of 10% or less (e.g. about 5%). The surface area of diffuser 19 is about 285 square inches.
Where the surface of revolution comprising the surface 14 is a partial ovoid instead of a partial sphere, as shown at 12' in FIG. 2, more than one radius will be provided. In this case the spacings of the element 11 and the second reflector 18 along the center axis 13 will be based upon the minimum radius as the value R while the dimensions of the reflector 18' may vary in proportion to the changing value of R. As illustrated in dotted line at 18' in FIG. 2 the periphery of the second reflector 18' mimics that of the first reflector 12'.
The interior surface 29 of the diffuser 19 has an outer periphery, shown generally at reference numeral 30 in FIG. 1, adjacent the first reflector 12. Sometimes it is desirable to roughen the interior surface 29 as illustrated at 30 to offset the effect of the index of refraction of the diffuser 19 on rays making an oblique angle with a normal to the diffuser interior surface 29.
FIG. 3 diagrammatically illustrates the diffuse reflection that is provided for the primary reflector 12 surface 14, as opposed to specular reflection. FIG. 3 illustrates an incident ray pencil 35 emanating from the source 11 to a surface element 36 on the surface 14. The reflecting surface element illuminates an element 37 of the diffuser 19 plane, as indicated by the illuminating pencil 38, in an amount which is proportional to (1) the area of the surface element 36, (2) the cosine of the angle θ between the surface normal 39 and the illuminating pencil 38, (3) the inverse square of the distance between the elements 36, 37, and (4) the cosine of the angle α between the illuminating pencil 38 and the normal 40 to the diffuser 19 plane. In specular reflection the cosine relationship (2) above is replaced by one which allows reflection at one angle only. The illuminance at the diffuser 19 is the sum of all the rays 38 from the surface elements 36.
FIGS. 4 and 5 illustrate a second exemplary embodiment of a light source assembly 10' according to the invention. Most of the components in the FIGS. 4 and 5 embodiment are the same as those in the FIGS. 1 and 2 embodiment and therefore are shown by the same reference numeral. The only significantly different element is the second reflector 42. In the FIGS. 4 and 5 embodiment the second reflector 42 has a feathered (or meandering) edge 43. The basic "1-2-3" (or "1-2-3.5") geometry from the FIGS. 1 and 2 embodiment is not changed if the feathered edge 43 is considered as an aureole added to the basic diameter (0.3 R) of the second area reflector 42, as illustrated in FIG. 5. In this case the secondary reflector 42 does not block all direct illumination of the diffuser 19 by the light emitting element 11, but rather some direct illumination--such as illustrated by the volume between the rays 45 illustrated in FIG. 4--of the diffuser 19, adjacent the first reflector 12 (that is at the periphery 30 of the diffuser 19) is provided. This allows the high uniformity of illumination of the diffuser 19 of the FIGS. 1 and 2 embodiment to be maintained while still utilizing direct rays (45) from the source 11, and eliminating any need for roughening (as at 31 in FIG. 1) of the diffuser interior surface 29.
It will thus be seen that according to the present invention an advantageous light source assembly has been provided. While the invention has been herein shown and described in what is presently conceived to be the most practical and preferred embodiment thereof it will be apparent to those of ordinary skill in the art that many modifications may be made thereof within the scope of the invention, which scope is to be accorded the broadest interpretation of the appended claims so as to encompass all equivalent structures and devices.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1219583 *||Jul 13, 1914||Mar 20, 1917||Ward Sumner Perry||Headlight-dimmer.|
|US1249133 *||Feb 15, 1915||Dec 4, 1917||States Lee Lebby||Projector.|
|US1279096 *||Dec 20, 1915||Sep 17, 1918||Harold G Fitz Gerald||Lamp or headlight.|
|US1302492 *||Jun 22, 1918||May 6, 1919||Albert L Arenberg||Lighting unit.|
|US1515221 *||Mar 10, 1924||Nov 11, 1924||Roberts Lynn T||Electric lamp|
|US1811782 *||Dec 31, 1929||Jun 23, 1931||Duncan Jr Thomas P||Light projector|
|US4288844 *||Aug 24, 1978||Sep 8, 1981||American Sterilizer Company||Electrically focused surgical light|
|US4463410 *||Jun 22, 1981||Jul 31, 1984||Kei Mori||Lighting device with dual reflecting members|
|US4584631 *||Oct 18, 1984||Apr 22, 1986||Prince Corporation||Indirect lighting for a vehicle|
|US4706173 *||Feb 20, 1986||Nov 10, 1987||Sharp Kabushiki Kaisha||Lighting apparatus|
|US4731713 *||Mar 24, 1986||Mar 15, 1988||Robert Bosch Gmbh||Fog lamp|
|US5128848 *||Mar 29, 1990||Jul 7, 1992||W.C. Heraeus Gmbh||Operating light|
|US5479328 *||Jan 5, 1994||Dec 26, 1995||Interstate Electronics Corporation||High-brightness, high-efficacy backlight|
|US5515255 *||Nov 14, 1994||May 7, 1996||Sterner Lighting Systems Incorporated||Lamp reflector|
|US5523930 *||May 12, 1993||Jun 4, 1996||Fritts; Robert W.||Fluorescent backlit displays or the like|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US6447147 *||Aug 29, 2000||Sep 10, 2002||Kramer Lighting, Inc.||Lighting apparatus with apertured convex inner reflector|
|US6661521 *||Sep 11, 1998||Dec 9, 2003||Robotic Vision Systems, Inc.||Diffuse surface illumination apparatus and methods|
|US7048424 *||Aug 14, 2003||May 23, 2006||Cross Match Technologies, Inc.||Light integrating column|
|US7144131 *||Sep 29, 2004||Dec 5, 2006||Advanced Optical Technologies, Llc||Optical system using LED coupled with phosphor-doped reflective materials|
|US7267461||Jan 28, 2005||Sep 11, 2007||Tir Systems, Ltd.||Directly viewable luminaire|
|US7329011 *||May 21, 2004||Feb 12, 2008||Seiko Epson Corporation||Light source unit, method of manufacturing light source unit, and projector|
|US7365991||Apr 14, 2006||Apr 29, 2008||Renaissance Lighting||Dual LED board layout for lighting systems|
|US7497590||Apr 26, 2005||Mar 3, 2009||Advanced Optical Technologies, Llc||Precise repeatable setting of color characteristics for lighting applications|
|US7604375||Apr 30, 2008||Oct 20, 2009||Advanced Optical Technologies, Llc||Optical integrating chamber lighting using one or more additional color sources to adjust white light|
|US7625098||Apr 25, 2005||Dec 1, 2009||Advanced Optical Technologies, Llc||Optical integrating chamber lighting using multiple color sources to adjust white light|
|US7654703||Apr 2, 2007||Feb 2, 2010||Koninklijke Philips Electronics, N.V.||Directly viewable luminaire|
|US7665867||May 1, 2007||Feb 23, 2010||Seiko Epson Corporation||Light source unit, method of manufacturing light source unit, and projector|
|US7712921||Dec 12, 2007||May 11, 2010||Seiko Epson Corporation||Light source device, method of manufacturing light source, and projector|
|US7828459||Oct 31, 2006||Nov 9, 2010||Abl Ip Holding Llc||Lighting system using semiconductor coupled with a reflector have a reflective surface with a phosphor material|
|US7845825||Dec 2, 2009||Dec 7, 2010||Abl Ip Holding Llc||Light fixture using near UV solid state device and remote semiconductor nanophosphors to produce white light|
|US7883239||Dec 23, 2008||Feb 8, 2011||Abl Ip Holding Llc||Precise repeatable setting of color characteristics for lighting applications|
|US7980728||May 27, 2008||Jul 19, 2011||Abl Ip Holding Llc||Solid state lighting using light transmissive solid in or forming optical integrating volume|
|US8021008||May 27, 2008||Sep 20, 2011||Abl Ip Holding Llc||Solid state lighting using quantum dots in a liquid|
|US8028537||May 1, 2009||Oct 4, 2011||Abl Ip Holding Llc||Heat sinking and flexible circuit board, for solid state light fixture utilizing an optical cavity|
|US8089207||May 10, 2010||Jan 3, 2012||Abl Ip Holding Llc||Lighting using solid state device and phosphors to produce light approximating a black body radiation spectrum|
|US8118454||Dec 2, 2009||Feb 21, 2012||Abl Ip Holding Llc||Solid state lighting system with optic providing occluded remote phosphor|
|US8142051||Oct 27, 2006||Mar 27, 2012||Philips Solid-State Lighting Solutions, Inc.||Systems and methods for converting illumination|
|US8162498||Mar 23, 2010||Apr 24, 2012||Abl Ip Holding Llc||Solid state lighting using nanophosphor bearing material that is color-neutral when not excited by a solid state source|
|US8172424||Oct 30, 2009||May 8, 2012||Abl Ip Holding Llc||Heat sinking and flexible circuit board, for solid state light fixture utilizing an optical cavity|
|US8201967||Nov 5, 2010||Jun 19, 2012||Abl Ip Holding Llc||Light fixture using near UV solid state device and remote semiconductor nanophosphors to produce white light|
|US8212469||Jul 3, 2012||Abl Ip Holding Llc||Lamp using solid state source and doped semiconductor nanophosphor|
|US8215798||Sep 20, 2011||Jul 10, 2012||Abl Ip Holding Llc||Solid state lighting system with optic providing occluded remote phosphor|
|US8217406||Dec 2, 2009||Jul 10, 2012||Abl Ip Holding Llc||Solid state light emitter with pumped nanophosphors for producing high CRI white light|
|US8282241||Jun 13, 2011||Oct 9, 2012||Abl Ip Holding Llc||Solid state lighting using light transmissive solid in or forming optical integrating volume|
|US8334644||Sep 20, 2011||Dec 18, 2012||Abl Ip Holding Llc||Lighting using solid state device and phosphors to produce light approximating a black body radiation spectrum|
|US8356912||Jun 16, 2009||Jan 22, 2013||Abl Ip Holding Llc||Lighting fixture using semiconductor coupled with a reflector having reflective surface with a phosphor material|
|US8360603||Sep 23, 2011||Jan 29, 2013||Abl Ip Holding Llc||Lighting fixture using semiconductor coupled with a reflector having a reflective surface with a phosphor material|
|US8422018 *||Feb 16, 2011||Apr 16, 2013||Otsuka Electronics Co., Ltd.||Optical measurement apparatus including hemispherical optical integrator|
|US8449137 *||Jun 29, 2011||May 28, 2013||Elumigen Llc||Solid state tube light assembly|
|US8651692||Jun 15, 2010||Feb 18, 2014||Intematix Corporation||LED based lamp and light emitting signage|
|US8686449||May 25, 2012||Apr 1, 2014||Intematix Corporation||Light emitting device with phosphor wavelength conversion|
|US8702271||Jan 30, 2013||Apr 22, 2014||Abl Ip Holding Llc||Phosphor-centric control of color of light|
|US8749131||Mar 4, 2011||Jun 10, 2014||Abl Ip Holding Llc||Lamp using solid state source and doped semiconductor nanophosphor|
|US8760051||Jun 12, 2013||Jun 24, 2014||Abl Ip Holding Llc||Lamp using solid state source|
|US8994269||Jun 20, 2014||Mar 31, 2015||Abl Ip Holding Llc||Lamp using solid state source|
|US9163802||Jul 14, 2010||Oct 20, 2015||Abl Ip Holding Llc||Lighting fixtures using solid state device and remote phosphors to produce white light|
|US20040130908 *||Aug 14, 2003||Jul 8, 2004||Mcclurg George W.||Light integrating column|
|US20050036314 *||May 21, 2004||Feb 17, 2005||Seiko Epson Corporation||Light source unit, method of manufacturing light source unit, and projector|
|US20050207166 *||Jan 28, 2005||Sep 22, 2005||Peter Kan||Directly viewable luminaire|
|US20060072314 *||Sep 29, 2004||Apr 6, 2006||Advanced Optical Technologies, Llc||Optical system using LED coupled with phosphor-doped reflective materials|
|US20060268544 *||Apr 25, 2005||Nov 30, 2006||Rains Jr Jack C||Optical integrating chamber lighting using multiple color sources to adjust white light|
|US20070047227 *||Oct 27, 2006||Mar 1, 2007||Color Kinetics Incorporated||Systems and methods for converting illumination|
|US20070051883 *||Nov 2, 2006||Mar 8, 2007||Advanced Optical Technologies, Llc||Lighting using solid state light sources|
|US20070138978 *||Nov 2, 2006||Jun 21, 2007||Advanced Optical Technologies, Llc||Conversion of solid state source output to virtual source|
|US20070242441 *||Apr 14, 2006||Oct 18, 2007||Renaissance Lighting, Inc.||Dual LED board layout for lighting systems|
|US20070274084 *||Apr 2, 2007||Nov 29, 2007||Tir Systems Ltd.||Directly viewable luminaire|
|US20070285630 *||May 1, 2007||Dec 13, 2007||Seiko Epson Corporation||Light source unit, method of manufacturing light source unit, and projector|
|US20080170308 *||Jan 12, 2007||Jul 17, 2008||Asml Netherlands B.V.||Cover for shielding a portion of an arc lamp|
|US20080186458 *||Dec 12, 2007||Aug 7, 2008||Seiko Epson Corporation||Light source device, method of manufacturing light source, and projector|
|US20080204888 *||Feb 19, 2008||Aug 28, 2008||Peter Kan||Optical system for luminaire|
|US20080205053 *||Apr 30, 2008||Aug 28, 2008||Advanced Optical Technologies, Llc||Optical integrating chamber lighting using one or more additional color sources to adjust white light|
|US20090296368 *||May 27, 2008||Dec 3, 2009||Ramer David P||Solid state lighting using quantum dots in a liquid|
|US20100172122 *||Jul 8, 2010||Renaissance Lighting, Inc.||Solid state lighting using nanophosphor bearing material that is color-neutral when not excited by a solid state source|
|US20100258828 *||Dec 2, 2009||Oct 14, 2010||Renaissance Lighting Inc.||Solid state light emitter with near-uv pumped nanophosphors for producing high cri white light|
|US20100259917 *||Oct 14, 2010||Renaissance Lighting, Inc.||Light fixture using uv solid state device and remote semiconductor nanophosphors to produce white light|
|US20100277907 *||Oct 30, 2009||Nov 4, 2010||Michael Phipps||Heat sinking and flexible circuit board, for solid state light fixture utilizing an optical cavity|
|US20110127555 *||Jul 21, 2010||Jun 2, 2011||Renaissance Lighting, Inc.||Solid state light emitter with phosphors dispersed in a liquid or gas for producing high cri white light|
|US20110127557 *||Nov 5, 2010||Jun 2, 2011||Abl Ip Holding Llc||Light fixture using near uv solid state device and remote semiconductor nanophosphors to produce white light|
|US20110128718 *||Jun 2, 2011||Ramer David P||Lighting fixtures using solid state device and remote phosphors to produce white light|
|US20110175510 *||Jul 21, 2011||Benaissance Lighting, Inc.||Tubular lighting products using solid state source and semiconductor nanophosphor, e.g. for florescent tube replacement|
|US20110175520 *||May 10, 2010||Jul 21, 2011||Renaissance Lighting, Inc.||Lighting using solid state device and phosphors to produce light approximating a black body radiation spectrum|
|US20110175528 *||Jul 21, 2011||Renaissance Lighting, Inc.||Lamp using solid state source and doped semiconductor nanophosphor|
|US20110205541 *||Aug 25, 2011||Otsuka Electronics Co., Ltd.||Optical measurement apparatus including hemispherical optical integrator|
|US20110255277 *||Oct 20, 2011||Mahendra Dassanayake||Solid state tube light assembly|
|EP2196725A1 *||Dec 4, 2009||Jun 16, 2010||Manfred Grimm||Lamp|
|WO2002018840A1 *||Aug 29, 2001||Mar 7, 2002||Van Colen Peter B||Apertured convex inner reflector for light fixtures|
|WO2005073629A1 *||Jan 28, 2005||Aug 11, 2005||Tir Systems Ltd||Directly viewable luminaire|
|WO2006039017A2 *||Aug 26, 2005||Apr 13, 2006||Advanced Optical Tech Inc||Optical system using led coupled with phosphor-doped reflective materials|
|WO2008098360A1 *||Feb 15, 2008||Aug 21, 2008||Peter Kan||Optical system for luminaire|
|U.S. Classification||362/300, 362/84, 362/307, 362/350, 362/303|
|International Classification||F21V7/09, F21V7/22, F21S8/00, F21V7/04|
|Cooperative Classification||F21S48/1394, F21V7/04, F21S8/00, F21V7/09, F21S48/1388, F21W2131/205, F21V13/12, F21V7/22|
|European Classification||F21S48/13D16, F21S48/13M, F21S8/00, F21V7/22, F21V7/09, F21V7/04, F21V13/12|
|Nov 22, 1996||AS||Assignment|
Owner name: AUSTIN AIR SYSTEMS LIMITED, NEW YORK
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LAWSON, LAWRENCE RICHARD;REEL/FRAME:008319/0191
Effective date: 19961121
|Mar 26, 2002||REMI||Maintenance fee reminder mailed|
|Sep 9, 2002||LAPS||Lapse for failure to pay maintenance fees|
|Nov 5, 2002||FP||Expired due to failure to pay maintenance fee|
Effective date: 20020908